Hello Leo and welcome ........
You are probably going to get several opinions on whats the best strategy, procedure and software for accomplishing this but the important thing regardless of what you settle on, is to do your backups and do them on a regular basis. I'll tackle an answer from a couple of different perspectives.
Personally, I would recommend adding a second, third or fourth hard drive to any machine and using it for backups. Yes, you can also burn DVD's or CD's or use a networked drive or a flash drive but my own preference is backing up to a hard drive and I use removable drive bays so those backups can be quickly removed and transported in an emergency situation. One can and also should burn copies of the backup data and images stored on a 2nd, 3rd or 4th drive and store those off site.
Software-wise, (again, my approach) I use Ghost to image the system drive about once a month and I image to the backup drive. Acronis True Image may be better software, but I still use an older version of Ghost. Secondly, I use Karen's Replicator to do daily automatic backups of important data stores. This is very well written freeware and is as good as it gets. My own approach is to make several backup folders on that extra drive and create several jobs using Replicator. For each job, one can select a source folder and a destination folder and schedule Replicator to run automatically - daily, weekly, monthly or whatever. You can filter file types for inclusion or exclusion and can elect to include or exclude file deletions from the source drive. If one wants to be real careful, several identical daily backup folders can be made, to provide 7 (days in the week) or more incremental folders of similar data backups. This may sound like overkill, but it brings one very close to a failsafe environment and provides several restoration/rebuild options in the event of catastrophic drive failure, system crash or other emergency. Both your images and your backup data stores can and should be backed up (using Replicator) to a networked drive in another machine or burned to CD's or DVD's.
I hope this doesn't sound too daunting because its a relatively simple procedure and will have you back up and running without a hitch on a brand spanking new drive in less than a half hour with no hiccups if your main drive ever gets totally hosed. I'm sure you'll get some other comments and suggestions but this is what works for me and its a well tested proven approach.