Just the thought of a duel-boot scares many people away, but over the years it's developed into an easier process. Most people are running Windows, so I'm assuming it's your choice of preference:
1.Re-install Windows. Look for a three line menu that reads something like; Do you want to install NTFS. Do you really want to install NTFS. The third line should read, Install FAT 32. These are just partitioning schematics.
Note: If you can not locate FAT 32, reboot and look for FAT 32 again. If you do not succeed the second time, repeat until you can locate it. At the current (07.27.05), installs tend to work in this manner. It's there, but you must go through this reboot procedure. When you locate FAT 32, install it. You will see it on a three-line menu, usually at the bottom. Install normally takes about 30-60 minutes.
After installing Windows, install the Linux CDs. It should recognize your FAT 32 Windows partition. On a three or four line menu screen it should ask you if you want to keep the FAT 32 partition. Click yes. It's that simple, with a good distribution of Linux.
When installing, always study the different installation screens whenever the system ask you if you want to install to a, b, c … drives. Writing this information on scratch pads, in case of mistakes, is also a good idea. With a good Linux distribution, you should be able to sail through the installation with nary a problem.