At present using Win 7 Ultimate, 7600 for about 3 weeks. Seems OK, so far. Had used another 7's version since late July but it had a limited bases built in. Vista was the reason the 7 series was developed, did not handle that well for a lot of people. XP, for most, handled much better. Gates is still trying to catch up with Jobs, and just about has with the 7's.
Should be no problem upgrading to & and keeping your file. Though the best way would be with a fresh start on your HD. Always carry some garbage when upgrading, it seems. Download the files on a flash drive, if you want to keep and add them later to the new OS.
After 22 Oct, I will load a more updated version of Win7. I have 4 different HD's, with different OS's on them. Might want to check out the Black version of Win 7 if you want more stuff which you probably really do not need anyway.