There are a number of good backup solutions on the market that are reasonably priced. We recommend Mozy for most home computers. Mozy is a on-line backup and can be set to backup automatically so it's likely to be kept up to date. It also stores data securely at an off-site location so is recoverable in even the worst case scenarios such as a house fire. And, Mozy offers up to 2GB free to each PC user.