I would burn the document folder to a CD. If you do NOT have a CD burner, you could try the transfer wizard on the Vista computer to get the files using a usb cable. If you don't have that capability, then you can always copy and paste the documents to floppy, if your new computer has the floppy capability.
I never used Microsoft Backup. I have always burned the important items that I wanted to save to a CD. If my computer went down today, I could pull out all my items from a CD. I also have a Windows XP SP2 CD along with drivers, in case of emergency.
Your last resort would be to email them slowly to your email account, but that's a PITA.
If you no longer have the old computer, then you are SOL.
Hope this helps.
Using the Microsoft Backup, I copied my Documents folder. They are backed up on 3 floppys. (My old computer used Windows 98, my new computer has Vista). I've tried numerous ways to copy and/or restore the information from the floppys to my new computer but to no avail !! For instance, if I simply copy the data, it's stored as "backup.qic". I can't get at the individual folders or files within the backup. Any ideas ??