After being unable to install SP2 for Ultimate, my computer now says that I have to re-install Vista. Is there a way to get my data from the computer before doing this. I was in the process of backing up all of my inventory for my store and it reset on its own.

You have to burn any liveCD for example Mepis Bypassing Log-in Passwords to Access Folders on Drive
(details in the link)

I just upgraded to vista ultimate sp1 32bit this past Monday (8/31/09). An update for SP2 was available and I chose download and install. It downloaded and began to install. At 93% the computer reset and stated the service could not install reverting back to sp1 (all this took about 10 hours). Everything was normal and the computer reset abruptly and upon logging in there was a message stating to re-install vista to re-activate it and it will not allow me to do anything. When I close the dialog box it logs me off. I tried to log on in safe mode and send the data to my cash register but my null modem doesn't work in this mode. I don't want to lose my inventory as I just finished inputting everything and as I went to back it up the computer reset. I hope I can fix this with the methods suggested. Thanks for the suggestions.

Problem Solved. Contacted Microsoft and was able to re-activate vista without having to re-install. The tech support member guided me through a system restore and said the problem was caused by corrupt files. Problem solved! Thanks Microsoft!