Copy & Paste or Canned Program Backup?

In the past I have tried using the Iomega program for my backup of files but it was quite confusing and I was never sure if the programs were actually backed up completely.
Then I purchased Bounce Back and had a computer problem and the guy that fixed the system said not to use those canned programs, and Bounce Back was a bit confusing as well.
Since then I have just been using the old copy/paste to move files from my system to a system backup external drive, but that takes some time as it recopies everything instead of just what has changed.
Any suggestions appreciated.
Candee