...I'm looking at doing the whole lot - complete image. Safer than picking and choosing, and then finding you forgot something crucial...
It's probably wiser to image the machine now and then only do so again when updates or installations etc have substantially changed the data. Clean the machine up and tweak it to your liking and take a "master" image. Then, every month or so or whenever said changes have occurred, take an updated image. Always keep at least two images and preferably store them in seperate locations.
I use Acronis for my imaging needs but there are free alternatives such as Easeus ToDo
Whatever imaging solution you use, it's vitally important to ensure that you verify the written images when they're taken and at regular intervals if they're to be stored for any length of time. Don't get lax about verification - I can tell you from experience that it will come back to bite you!
Personally, I don't actually install Acronis for any longer than it takes to create a few TrueImage boot CD's. I don't see the need for it as the bootable media are more than adequate for my needs.
I've not used Easeus but I believe that it's broadly similar to Acronis TI. Depending on what backup medium you choose, you may find that an imaging program is supplied with it.
Taking images doesn't take long but on a daiy basis, it can become a bit of a bind so for day to day user data backup, something like Karen's Replicator
can be set up to back up what you want and if you wish, scheuled to run at convenient times. Again, if these data are sensitive or valuable, they should be backed up to at least two (Preferably physically seperate) locations.
At home, I have a couple of Lacie 500G NAS's and a couple of Seagate 500G USB drives. If I'm out and about, I have two 500G SATA 2.5" enclosures plus a variety of thumb drives. The 2.5" enlosures are very handy as they can easily be slipped in a laptop bag or even a pocket.