RE: what should i buy
 

I think that either are great all around calibers, the 30-06 has the advantage of heavier bullets which is where your OOMMFF comes from. also they are cheapto shoot, I'd still use premium loads when actually hunting. good luck.

RE: what should i buy
 

The 30-06 will handle whitetails, and a lot more, including elk/moose. However, you also
noted you wanted something with more "ummph". While the '06 has plenty of "ummph", the 7mm Rem.Mag. is a little better in terms of longer ranges (flatter trajectories).
I'd recommend you take a look at a Ruger 77 MKII. They're reasonably priced rifles,
and available in either 30-06 or 7mm Mag.

RE: what should i buy
 

My favorite is the 7mm Mag. Very accurate with exceptional long distance performance. Oh, as far as the myth on recoil. The 7mm Rem. Mag. puts out 19.1 of recoil energy with a 150 grain the 30-06 20.3 re with a 180 grain. I would say the recoil is comparable. ;)

RE: what should i buy
 

Only one rifle? Get the '06. It is far more versitle than the 7mm and it can handle everything from varmints to moose.
You won't be sorry.
And if I were to select a rifle, it would be a Savage bolt action with the accutrigger. Great out-of-the-box accuracy and less expensive than most of the other manufacturers. The money you save on the rifle, you can put toward a better quality scope.