You may have to do a clean full install. Windows XP uses a bootstrap process that then loads a program called NT_loader. The NT_loader program is usually placed somewhere in the middle of the hard drive. Your abortive Linux install may have over written that section of the hard drive and rendered the computer unbootable.
Give this link a try for your one last attempt before doing the re-install of windows.
I would also suggest that you try a more stable version of Linux after you have re-installed XP.
I am using Conectiva 10 in a dual boot with Win2k. Please remember that Windows likes to have a hard drive all to itself and it prefers to live in a hard drive named C:
Linux also likes to have a hard drive all to itself but it doesn't really care what you call the hard drive.
If you are going to dual boot from the same physical disk. You have to partition the disk so that there are two seperate logical drives.
One called C: for windows
And one called L: for Linux.
I believe that there is a partition tool on the UBCD. I suggest that you use that to create the new partitions for the logical drives.
If all else fails you can ask the people in this forum for help http://p090.ezboard.com/btotalseminars
They are primarily A+ & Net+ windows techies may be able to help you with your problem.