If like me you are an inveterat tinkerer, then there are a couple of things that are in my opinion very important.
1. Keep all data on a separate partition so that if the OS goes tits up then you can reformat/reninstall without risk to the important stuff - i.e. your data.
2. Take a look at HyperOs. It is a systems multiplier that allows you to install multiple copies of the OS and make backups of the complete OS partition so that if it all goes wrong you can restore the whole set up in seconds. Visit their site, click here and make sure you read the somewhat longwinded section on "benefits to you". I've had it for over two years and never had a windows crash that wasn't my own fault. Both times I copied back the backup and was up and running on exactly the same system (minus the problem I induced!) within 2 minutes. It is not real cheap, but well worth the money.