See if this is a bit more informative for using the back up and restoration program that is built into vista

http://www.microsoft.com/technet/tec...p/default.aspx

There should not be any drive letter problems....the partitions will retain the named letter designations...like the title of a book...doesn't change. When you remove 'D' and reinstall.....the system should install as "C" or local drive..."D" would become the main optics drive...."E" would remain......all others would be renamed as needed.....

If it does change....all you will need to do is to change the partition back to "E" and all other pathes should be ok from within.

Remember though...this takes TWO actions complete deletion of xp partition and new installation of vista to that partition....then the second action is to believe that the new installation is corrupted and you will use the restore capabilities of the new vista installation to revert back to the back up copy.......that should keep all pathes and links the same as before.