junior, a 3-9 power is a pretty flexible scope and I doubt if you could go wrong.
Another thing to think about is the second number in the size of a scope. For example, you can get a 3-9 x 33 or a 3-9 x 40 or even 50. This second number is the Objective Diameter. This is what controls the AMOUNT of light that gets into the scope. The bigger the number, in general, the brighter the picture in the scope. This becomes important in low light situations or even in night hunting over feeder lights.
So why not just get the biggest Objective Aperture that you can afford? Well, you may just be throwing money away because you don't need that much. Also, the bigger this dimension is, the higher above the bore the center of the scope sits. This becomes a problem when trying to comfortably shoulder the rifle and get a good cheek weld as well as making the sighting in a bit more complex due to trajectory (my opinion).
I have looked through a huge Trijicon scope on a friend of mine's 30-06. We were in a parking garage on a cloudy day, and I could see anything I pointed it at without any problems. But, it was huge, bulky, and much more than I would ever need for hunting.
I personally prefer smaller scopes that sit low to the bore and are comfortable to use.