Are you willing to pay or do you want freeware? It will make a difference to the answers you will get. Paid for = Acronis True Image Home 2010,
Freeware = I could not recommend any one over any other, I would stick with the Windows default program.
I have backed up with a few different programs over time but have never used the back up to restore my PC. I have always just done a clean install and then copied my data back that I have saved to a DVD.
I believe that most programs will work very well and will restore your PC if necessary. Therefore, I have not used any (to their full extent) and found them to effective or ineffective.
I just installed and tried acronis a day ago,have been fiddling with it all day,after I had done the complete disk image,was trying to set up incremental backups without backing up all my pics and all my music again but I can't get that figured out.
But it did a perfect job on the disk image.It's free for 15 days but once you get the image made then you are home free,unless you want ot do backups,then you need to purchase it.