You now have a fully patched operating system, with new software installations and updates managed via Adept and Automatix. It's time for some final polishing.
I have found dozens of guides, how-tos and tips referring to the installation of the graphic cards. Some are well written; others less so. Sincerely, I cannot recommend any of them, because the individual tweaks written in each one of them may not apply to your system and could only contribute to confusing you. For this reason, I will not link to any specific source explaining the below procedures. I have tested the Nvidia setup without a glitch. I did not have the opportunity to test the ATI drivers.
Your best choice should be the Ubuntu forums, Unofficial Ubuntu 6.06 (Dapper Drake) Starter Guide and the search engine of your liking.
Before you install your graphic drivers, backup your existing X Windows configuration. This way, if something goes wrong, you will be able to get back to your original configuration by copying back the file.
sudo cp /etc/X11/xorg.conf /etc/X11.xorg.conf_backup
If you have an Nvidia graphic card, open a Terminal and type the following commands:
sudo apt-get install nvidia-glx
sudo nvidia-glx-config enable
Reboot. You should see the Nvidia splash screen during the reboot. You can also use Automatix to install the drivers.
If you have an ATI graphic card, you should do the following:
sudo apt-get install xorg-driver-fglrx
sudo apt-get install linux-restricted-modules-`uname -r`
sudo reboot now
sudo aticonfig --initial --input=/etc/X11/xorg.conf
sudo reboot now
After installing the graphic drivers, you might want to change the screen resolution and the refresh rate. Unfortunately, unlike SUSE, (K)ubuntu does not have an elegant way of achieving that.
To change the screen resolution and/or the refresh rate, please refer to the guide on Ubuntu forums. Very importantly, do not forget to test your new settings before applying the changes - you may lose the screen or even damage the monitor.
Alternatively, you can use the Package Manager to install the graphic drivers. This way, you will not have to reinstall the drivers after a kernel update.
Finally, you can also try Alberto Milone's envy package, which will detect the model of the graphic card, download the right version, build the necessary dependecies, install the driver, and setup the X Server. The package works for the Nvidia and ATI cards.
If the computer with Kubuntu installed on it functions as Internet gateway for several other machines, you might like to enable other computers to connect to the Internet through it. You should try the How to share Internet connection guide on Ubuntu forums. You could also try to setup the sharing on your own using the System Settings.
K Menu > System Settings > Internet & Network > Sharing
Basically, this should not be significantly different from setting up a sharing in Windows. You should also refer to my article called Highly Useful Linux commands & configurations; among many other things, sharing of network resources between Windows and Linux and vice versa is explained in detail there.
You will be able to tweak your operating system by accessing System Settings under K Menu.
This panel will allow you to change your personal, hardware or administrative preferences. It is very similar to the Control Panel in Windows or YaST in SUSE. Once again, some basic knowledge in working with other operating systems will greatly help you become quickly accustomed to Kubuntu.

One of the questions that most Windows users ask when trying Linux is: "Will my Windows stuff work?" Usually, they refer to audio and video codecs, flash, java, and similar content. The answer is that all these can very easily be obtained and installed.
Here are a few guidlines that will make your transition so much smoother:
Note: For the more recent releases of (K)ubuntu, you should try Unofficial Ubuntu 7.04 (Feisty Fawn) Starter Guide or Unofficial Ubuntu 6.10 (Edgy Eft) Starter Guide. You will notice that there are many similarities between the guides.
Let's see how you can quickly and painlessly obtain your favorite Windows toys. The examples below are taken from the Unofficial Starter Guide. They require the use of the command line, but you should be confident enough by now.
sudo apt-get install gstreamer0.10-ffmpeg gstreamer0.10-gl gstreamer0.10-plugins-base \
gstreamer0.10-plugins-good gstreamer0.10-plugins-bad gstreamer0.10-plugins-bad-multiverse \
gstreamer0.10-plugins-ugly gstreamer0.10-plugins-ugly-multiverse w32codecs
The backslash indicates that the command continues in the line below. If you are not comfortable with such lengthy commands, you can install each of the codecs separately.
sudo apt-get install sun-java5-jre sun-java5-plugin
You will have to agree to license terms. Upon installation, you will need to configure the plugin to be used as the default Java Virtual Machine.
sudo update-alternatives --config java
sudo apt-get install flashplugin-nonfree
sudo update-flashplugin
Going over the entire repertoire of goodies is almost impossible, but some applications merit a special mention. As a new Kubuntu user, you will probably wonder what programs you should use and what they offer, especially in regard to your familiar Windows turf.
Below is a very, very short list of some of the more popular KDE applications. Depending on your installation, some of these might (or might not) be installed. But they can easily be obtained, either from home sites or via the package manager.
Amarok - this is a light, simple, beautiful, and highly versatile for Linux
running KDE; natively, it does not support MP3 format, but the necessary libraries can easily be added - for
example, in Ubuntu or SUSE, via package managers - libxine-extracodecs.
Blender - a 3D creation tool, with excellent animation, rendering, and
physics tools (and many more).
K3B - is a superb CD burning utility for KDE, with lots of excellent features,
including support for multiple El Torito boot images, audio CD burning, VCD, SVCD, mixed-mode CDs, eMovix CDs, CD
copy and CD/DVD ripping, DVD burning, DivX/XviD encoding, blanking of CDR-Ws, writing of ISOs, and a whole lot
more.
Kate
No, you guessed wrong; it is not a Japanese WW2 torpedo bomber. It is a very powerful text editor.
Kino - this advanced video editor allows integration with
IEEE-1394 for capture, VTR control, an ability to capture video in Raw DV and AVI formats, with doth type-1 and
type-2 DV encodings, an ability to export composite movies in still frames, WAV, MP3, Ogg Vorbis, and many other
formats.
Koffice - is a full-featured, integrated office suite for KDE, offering 12
different applications, with standard office word, spreadsheet, database, and presentation programs, but also
flowchart, image manipulation, project management, formula editing, and business quality tools.
Konqueror - Konqueror is a combined browser and file manager for KDE.
Kontact - is a personal information management suite; it includes the KMail
email client, KOrganizer calendar component, KAddressbook address book management tool, KNode news reader,
KitchenSync, a synchronization framework for mobile devices (phones, PDAs), and many other useful tools.
Kopete - an Instant Messaging program for KDE; Kopete supports AIM, ICQ, MSN,
Yahoo, Jabber, IRC, Gadu-Gadu, Novell GroupWise Messenger, and more, as well as message encryption and
archiving.
KTorrent - BitTorrent client for KDE.
This list is just the tip of the iceberg. You can refer to Kubuntu Desktop Guide for detailed explanation how to use and configure the KDE desktop. In particular, Chapter 4. Common Tasks, contains a wealth of information regarding the KDE applications, including music, video, CD/DVD burning and ripping, graphics, Internet, Office, Programming, and more.
Finally, you should also read my article called A (cool) list of Linux tools. It contains links to a variety of Linux programs, sorted by categories, including many KDE applications (some of them already mentioned above). Each listed item is accompanied by a short explanation regarding its basic functionality. There is also a users' corner, with suggestions from my readers.
That pretty much covers the basics. If you have followed this guide, with some luck, you have by now mastered:
Kubuntu is a compact, robust operating system that is well suited for the beginner-level users. It is a great tool for getting starting with Linux, learning the basic concepts and overcoming the fear of the dreadful *nix world.
The rest is up to you.
Ubuntu
Kubuntu
Xubuntu
Ubuntu forums
Unofficial Ubuntu 6.06 (Dapper Drake) Starter Guide
Unofficial Ubuntu 6.06 (Dapper Drake) Starter Guide -
Networking
Automatix official site
Introduction to Automatix on Ubuntu forums
Step-by-step Automatix installation guide on Ubuntu
forums
Step-by-step Automatix installation guide on
Automatix official site
How to change resolution and refresh rate in Xorg
Testing the Xorg
configurations
How to share Internet connection in Ubuntu
Kubuntu Desktop Guide
Using DSL with Linux
Ubuntu Linux Resources
How to install ANYTHING in Ubuntu!
Ubuntu Linux Resources on psychocats.net
Unofficial Ubuntu 6.10 (Edgy Eft) Starter Guide
Unofficial Ubuntu 7.04 (Feisty Fawn) Starter Guide