You made a great choice with the ProHunter. Are you going to be using a scope on it? I have an original Encore and I know they say that shooting 200 yards is not a problem. (I personally wouldn't shoot this far until I spent a lot of time at the range at this yardage.)
If you think you'll be shooting over 125 yards I'd go with 150 grains of either Triple 7 or Pyrodex. I shoot only 100 grains but my shots rarely reach out to 100 yards. The Triple 7 is a little cleaner to shoot. I would get the new Triple 7 209 primers or Remington cleanbore primers. These cost a little more but they are supposed to cut down on the famous "crud ring".
As far as bullets go, you'll have to find what shoots best in it. I would try Barnes MZ Expanders in either 250 or 300 grain. I have used the cheap T/C XTP sabots and have killed 2 deer with the 240 grainers. I'll PM you some other info.

Mike