Yeah, 5 fps is pretty much standard. Much more and you dont have enough space, although, space is cheaper and cheaper these days. The pizza folks named their budget and I pared it down to what would work for them. 4 cameras, network H.264 DVR, IR's on the cameras...standard deal. I even used pre-made cable to save on labor, don't hate! You gotta do what you gotta do sometimes and they are a new store, family folks and I'll be there for them when they want to upgrade.
Anyway, to your questions: usually, you set up each camera to record the way you want it to record individually. So your one tight shot of exit (I always get shots of people going out rather than coming in, if someone comes in with ill intent they're keeping their head down and probably a hat or hood, watching them go you'll see them looking out the door and much less guarded), so you set that one up at your highest resolution, higher frame rate if you want (everyone says 5fps is more than enough) and get a varifocal lens and good DSP/CCD whatever. This thing looks like a beast and probably overkill but it's along the lines of what I mean: http://catalog2.panasonic.com/webapp/wcs/stores/servlet/ModelDetail?displayTab=O&storeId=11201&catalogId=13051&itemId=105037&catGroupId=14459&surfModel=WV-CW484S/15
Some of those plug in units with the pig-tail splitter deals work ok, you just have to look at the power to drive each camera and see if the power supply gives you enough amperage, or mili-amperage.
I almost sound like I know what I'm talking about!