Hmm... could you possibly try System Restore. All new windows operating systems have it.
Find it in Start, Accessories, System Tools, System Restore.
Say to go back to a point, and hopefully your computer was set to make them once every few days, so go back to the newest one and hit okay.
You'll lose some of the registry though, so if you installed any programs up to that date, they wouldn't have deleted, but they won't be in the start menu nd might nto run right, etc. but documents and things will still be all fine, so dont worry.
Hopefully when the computer boots back up, it'll be there again, and hopefully will stay that way
To check settings of System Restore, go to Start, Settings, Control Panel, and then to System, and finally to the System Restore tab.
Here you can select drives you want it to monitor and create spaces for so you can revert back, and clicking settings allows you to select the disk space to use on creating them (put it as high as you can if its a big drive as you wont be sorry doing this)
To clear unwanted restore points your computer has made over the coming years you can select to turn off system restore, and then switch it back on again which would wipe all of them its created. Don't do this before reverting back though, and I think it deletes old ones automatically anyway
So good luck, and I hope this erm...s.a helps