I just wanted to add a comment here..
I never worry about backing up program settings or registry, etc.
For me I worry about 2 things (as i described in my old
backup guide):
First, i make sure my personal documents are backed up, OFTEN. This includes any real writing i may do or programming, etc. It's anything that i hold near and dear to my heart that would make me cry if i lost it. It does not include things like program settings which would suck to have to reconfigure but wouldn't be the end of the world.
Second, i make a full system drive image regularly (but not as often as i backup my documents). This is in case my entire system crashes, i lose a hard drive to a hardware fault, or in case something else infects my PC.
If something catastrophic happens, my solution would be to reinstall from a stable drive image, reseting the entire hard drive to a known good state. I do not trust the idea of "partially restoring" the system by running windows built in system restore, or trying to restore a saved registry... it all seems to fragile and error prone to me.
The backup of my documents are meant to provide a good history for me of all my personal work so i can always restore a recent version of these files at any time, including after a drive image restore. And to let me find an older version if i mess up something.
In short, i recommend not relying on anything fancy -- better to do a full drive image on a regular (monthly?) basis, and be prepared to go back to that state if something goes badly wrong with your pc. And combine that with a daily/weekly backup of your own personal documents which are most important to you, using whatever program can do that quickly (and keep versioned backups so you can find older versions).