Just because you're new to rifles doesn't mean you should pick a "starter' caliber. I'm not suggesting a magnum either, just consider what hunting you are likely to do in the future. Have you shot any rifles? Do you consider yourself to be recoil shy? If not, you may want to consider any of the "standard" deer calibers. You really can't go wrong with a 270, 308, 30/06 etc. What I'm saying is, folks tend to think rifles kick more than they do. If you bought a 243 just because you believed you couldn't handle a 308, you may wish you had a bit more power at some point in the future. Beg, borrow or whatever, and try some before you select a caliber.

First, I would figure out what type of rifle you like best, lever, bolt, even a pump. Then I would go for a caliber that you can easily find ammo for. You may end up with a lever in 30/30, 35 Rem, 308 Win, 358 Win, 375 Win. Or, a bolt in whatever caliber. They'll all work.