I use Acronis True Image 10. As disk-imaging software, it takes a ‘snapshot’ of any of your HDs (including the OS, of course) and also does incremental & differential backups. The software is fairly inexpensive & easy to use. It can also backup & restore any Linux partitions on your system.
If its a win XP Pro…Backup software comes inside…u will find it under Start > Programs > Accessoris > system tools > Backup… you can shedule nd do lots of stuff.
I havent used VISTA yet so cant tell you if this function is availabe in it or not.