Instead, I would recommend you start migrating to open source Windows applications in Windows, playing around with Ubuntu virtually inside Windows, and then use a dual-boot between Ubuntu and Windows.
If you are using Mac OS X, the community documentation may help you out here.
Now that you have the Desktop CD, you’ll need to reboot your computer to use Ubuntu.
Your computer’s BIOS must be set to boot from CD first; otherwise, Windows will just load up again. To get into the BIOS settings, you usually have to press one of these keys during boot-up: Escape, F1, F2, F12, or Delete. Usually your computer will tell you which key to use.
If you have at least 512 MB of RAM, you may want to select Try Ubuntu without any change to your computer, as it will allow you to do other things (check your email, browse the web) while you’re installing Ubuntu.
If you have only 256 MB or 384 MB of RAM, you should select Install Ubuntu. This will give you the same installation screens you see below, but you won’t have the rest of the Ubuntu live session running as well.
If you have less than 256 MB of RAM, you should use the Alternate CD to install Ubuntu, or do a barebones installation.
By default, the installer will give you the option to install Ubuntu side by side with whatever operating system is currently on your computer. You can choose that if you want to set up a dual-boot, but as I stated before, the safest dual-boot is probably with Wubi, unless you know what you’re doing (in which case you shouldn’t be looking at this guide).
For simplicity’s sake, you should select Use the entire disk. Or, if you don’t want to erase your entire drive, click Quit and then boot back into Windows and set up a dual-boot using Wubi.
If you are concerned about ever having to reinstall Ubuntu, but you want to make sure your user settings and files are preserved, check out these details on creating a separate /home partition during this part of the installation.
After you reboot, don’t be alarmed if you see some text boot messages. Just wait for Ubuntu to load…