http://www.vistabootpro.org/
It's a one time fee of $9.95 and it is the best multi boot agent.....i think it's called dual boot pro now or something. But, you get to name the drives and os's whatever you want as well as the hdd's. Win 7 RC I think will only work for a little while longer anyways.
Do not waste your money on this. You can do it for free with any partition editor, like fdisk or gparted.
Furthermore, dual booting XP/7 is easy.
I will walk you through the steps real quick.
1) Download
Infra Recorder or
ISO Recorder (I prefer the former).
1a. Open Infra Recorder and click the 'Write Image' button in the main screen. Select the ISO file, then click "Open". Hit "Okay" in the dialog. Wait for the burn to complete.
1b. On ISO recorder, right click the ISO file, select the burn option, then follow the instructions on the screen.
2) We need to partition your system for dual booting. I personally use a
Ubuntu live cd to edit partitions. This is alot easier than using fdisk. Burn the Ubuntu live CD using the steps in part 1. Then, reboot your computer with the CD in the drive. When it pops up, do not hit anything. 30 seconds later, it will load the live CD. DO NOT HIT INSTALL. This will install ubuntu. We don't want that. Instead, go to "System" on the top nav bar, then to "Administration", then to "Partition Editor". We are going to want to create some free space for the 7 install. Click on your XP partition, hit "edit", and decrease its size by the size you want the 7 install to be. Hit okay, then, click the free space, hit "New", and create a NTFS partition the size you want the 7 install to be. Shutdown the computer and remove the live CD.
3) Insert your Windows 7 CD. Follow the on screen instructions. When prompted, select to install 7 side-by-side with XP, instead of upgrading. Select the second partition for this purpose. Wait for install. Enjoy.
If you have any problems, or need any help, click the "Tech Support" link in my sig. Someone will be able to help you.