Thanks. But, I think I would prefer not to try reconfiguring the Windows XP bootloader.
You're going to either have to replace it or reconfigure it, unless you want to get a boot floppy, or CD working... You can have grub chain load and boot the Windows NT boot loader, or you can configure Windows XP to boot Linux and/or load grub.
In your situation where you have a working copy of Windows pre installed, and are not completely familiar with what you need to do, I would take this approach.
Wipe, and reinstall Fedora. It's not completely necessary, but it will get you to the right place in the most certain manner. This time though, instead of installing grub to the MBR install it to the partition you are installing Fedora on. (I think you said you already did this part, installing it to /dev/sda6?)
When you reboot, because you have not mucked with the MBR you will once again boot into Windows. Your best and simplest bet is to read the fairly straight forward documentation and examples for bootpart at this website, http://www.winimage.com/bootpart.htm, and use it to configure the nt bootloader. It puts a one liner in c:\boot.ini and creates a file with a copy of the linux boot record to get the boot process started.
The configuration is actually stored in a text file c:\boot.ini, so if you back it up you can always get back to the beginning if you muck things up, and while your mileage may vary, I seriously doubt it will get you to the point where you cannot boot Windows.
Hope this gets you pointed in the right direction, Jason