^ This, when you are shooting actual film the camera itself doesn't make all that much difference, so long as the seals are good on it and you don't get any light leak. It sounds like it'd be an easy fix if you got one with a damaged seal, it's not. So I'd say if you buy used, make sure you can give a good inspection first.
Beyond that, the lens usually makes it or breaks it, and Nikon is nice because to my knowledge all their lenses are completely interchangeable. For starting out, I'd recommend the fastest normal lens you can afford. (Normal meaning non telescopic, regular field of vision. / Fast meaning widest aperture [lowest f-stop].) This gives you awesome capabilities for altering field of depth in your photos, and opening up the aperture, you can get amazing low light shots with minimal film grain.
Just understand that most of this stuff is learned though doing, and don't become discouraged, your first few rolls of photos in all likelihood are going to suck. Keeping a log of what shutter speed and aperture, and in what conditions you were shooting is great. Then you can review and know how to better adjust.
You probably already knew a lot of this, but it's just easy to go in thinking it will be similar to the point and shoot ease the digital era has many 'photographers' used to. Not even the same league, but well worth the reward once you get it down.
