How long of a shot are you anticipating to make?
The classic 30-30 has killed more deer than any other caliber AFAIK. Good for 100 yard shots, I've seen folks kill deer with them at 200. I've killed a number of deer with one between 100-200 yards.
Now, I've got a .35, which is like a 30-30 with a little extra oomph.
http://www.marlinfirearms.com/Firearms/centerfire/336C.asp Where I hunt primarily, it's freakin perfect. Up to 100 yards it hits like a sledgehammer, it's made the last few deer I took do a flip in the air when they're hit (like something out of Hollywood, no kidding) It's a slow moving, large bullet, a great brushcrasher.
I've also got an old 30.06, a sporterized Eddystone 1917. I use it for hunting in places where I'll have a longer shot. It's also an ironsight gun (like my .35), I inherited it from my great uncle. He hunted bear, muley's and elk with it for years. I've only killed a few varmints with it, not yet had the chance to take a deer with it.
My next rifle will be a .308 Tikka T3, and likely a .204 Tikka for varminting and target shooting. These will get scopes though. I'm hoping to put one of them together for next season, after the Mrs finishes school, and some money frees up.