What kind of computer is it, I know some of them include recovery software. You take my Samsung Netbook for example. Samsung Recovery III software, it works great. It will take a snapshot at any given point and burn it to 2 to 4 DVD depending on how much stuff you add. I recently switched to Win 7 and decided I wanted to go back and BAM 20 minutes I had done a full restore and it had all my software loaded and allowed me to take up exactly where I left off. I also created one of Win 7 in case I decided to go back to that. Which low and behold I did do.
I also have Windows Home Server which creates a image and is updated every night and it will allow you to do a restore from any given point as well.
HP makes a nice recovery program as does Lenovo.
When I was running Vista I had Vista Business and it includes the Microsoft Backup program, but I found it slow, slow, slow, did I say it was slow.. my gosh it would take hours to back up and hours to restore. Microsoft doesn't do backup very well, so not having it is likely a blessing.