Okay rim going to show you how to dual boot Linux and windows vista or XP anyway lets start.
Installing Linux:First off we need to create a new partition for Linux.
So press start and search for Computer Management, click on the result, or you can run compmgmt.msc.
On the left hand side there is a list, click Disk Management.
When thats loaded you should see all your drive(s), find your primary one the one that vista or XP is installed on, right click on that and then click "Shrink Volume", i would recommend doing 10GB +.
Now turn off your computer and install your Linux in the partition you just made, i haven't tried this with anything other than Ubuntu, Ubuntu lets you use the grub bootloader to boot either windows or Linux.
Removing Linux:
If you want to remove Linux, you do not delete the partition or you will be unable to start your computer, what you want to do is download this program called EasyBCD, this will allow you to replace either your Vista bootloader or your XP bootloader, you can download this from
http://neosmart.net/downloads/software/EasyBCD/EasyBCD%201.7.2.exe.Once you have done that and installed the program click manage bootloader, then choose either Reinstall Vista Bootloader for vista, or Uninstall the vista bootloader for XP, once you have chose one then click "Write MBR".
I hope you have enjoyed this tutorial, and have fun dual booting.