Do all iPod's have a camera on the front?
No. the Ipod Touch 4 gen. is the only iPod touch w/ a camera. But the iPod Nano 4 and 5 gen. also have one (note: not all iPod nano 4 gen. have a camera.) Im not so sure the iPod Nano 6 gen. has one, tho.
The hard drive capacity of the iPod does not tell anything about the iPod, except its hard drive capacity. There are numerous generations for all of the types of iPods available, so please be more specific. The fifth generation iPod Nano has a video camera, and the fourth generation iPod Touch has a video camera and regular camera.