Try this, install Ubuntu as another program within Windows XP through Ubuntu's WUBI installer. just create the CD and start the Auto Run off the CD. The Installation will give you 3 choices. Install Ubuntu over Windows, install along side of Windows using the remaining disk space, or one to "test" ubuntu is to install within Windows.

The 3rd is the safest. If you have a "FAST" computer you won't notice any slowness from Ubuntu, but it'll install like Office on your computer. The installation even asks for the initial user name and password that you will be using. Once complete, reboot. Wubi will ask if you want to boot to Windows or Ubuntu (windows by default if nothing is pressed).

If you want to remove Ubuntu, just go to Add/Remove programs and uninstall Ubuntu. That's it, you'll get everything back. Oh, during the installation, it will ask how much HD space you will allocate, 8gigs standard.

Now, if you want to install onto another Partition, the Wubi installation that states installing next to Windows should give you the partition option where you can install Ubuntu onto.

Have fun.

I've been running an Ubuntu Server for years, I'll never install a Windows server for personal use ever again. The best part, is gaining full access to the server from my Android phone.

When installing from the live CD:

at this installation step: http://www.ubuntu.com/sites/default/files/active/03_global/09_instructions/install_04_medium.jpg

Select "Specify partitions manually (advanced)".

You can then choose, create and delete partitions.

To install Ubuntu on a specific partition, select it and specify "/" as mount point. You can choose ext4 or ext3 filesystem for this partition.

Be sure to create a small swap partition too.