Erik Jacobson , Jun 04, 2010; 11:57 p.m.
I wouldn't recommend someone with no background knowledge of cameras to buy a used camera, due to the fact that you may overlook some important things to check before you buy it.
I would also assume that the rebels such as the T1i T2i etc would be probably the most user friendly.
However I did completely the opposite. I bought everything used, and went with a 20D instead of a rebel.