That's a lot of cropping. You're definitely going to lose image quality if you want to enlarge it enough to make the deer the main subject of the pic.
It will work if you don't mind a bit of noise (grain)
Once you've done that. Sharpen the pic and beef up the contrast.
ok I have another question. Would you be able to crop and zoom into a certain spot on a film picture better than a digital?? Maybe a stupid question but I don't know a whole lot about photography, just bought a d80 last year because I always seemed to see things that would make good pics when i was hunting. Seems like since I bought I haven't saw anything worth taking, funny how things do that huh :-(
You might get a smidge more detail out of film at ISO 100, but at higher ISOs 35mm film will be the same or worse than most DSLRs. You need more focal length. You might also look into teleconverters.
I've gone out photographing with groups of hunters, and the first thing I noticed is that I needed to get way closer to my subjects to photograph them than they did to shoot them. To get the sort of magnification to fill even a quarter of the frame at the shortest rifle ranges you'll want to look at focal lengths of 1000mm and longer. With 200 - 300mm you have to be able to get pretty close.