I use a cheap 2-man tent (really, about 1 1/2 man) simply so I have room to thrash. What's really important for novice campers, I think, is room to sit up inside comfortably - makes changing clothes, etc lots easier when it's raining!
Ha, no. I have a tiny tunnel tent. You can't sit up without pushing your head against the mesh ceiling. But so what? Pretty much the only thing I do in there is spread out my gear and go to sleep. I'd much rather save a few grams of weight, even if it means I'm getting changed outside or something...
Steve