If and when you get things sorted I'd thoroughly recommend investing in a decent disk imaging program. Paragon and Acronis both produce decent utilities - and earlier versions are often given away free on computer magazine cover disks. These programs allow you to save an 'image' of your hard drive or partitions which can then be re-written to the hard drive in the event of a disaster ( such as a failed service pack installation! ). They also often come with a utility that allows you to make a bootable CD which will allow you to access your saved images in the event of the OS being unbootable.
I'd also recommend partitioning the disk to create a separate partition in which to store any backup images - and again, some of these imaging programs contain tools that can repartition your hard drive without destroying any data.
Sounds like a lot of hassle until you consider that had you had all this in place you could have restored your OS in about as much time as it takes to make a decent cuppa and a bacon butty.
Keeping up-to-date backups is the cutting edge of DIY...
Regards,