When choosing a scope for hunting there are a lot of things to take into consideration. First what caliber of rifle will you be mounting the scope too. What animals will you be hunting with that particular set up. And the power of the scope as to the conditions you will be hunting. Last but not least is your budget, get the best scope you can afford. Its not worth it to put a twenty dollar scope on a five hundred dollar rifle.
Caliber, if using a.22 for squirrels, a 2x - 6x scope should perform well, because most shots are from 20 to 50 yards. For a larger calibers like a.243 - 30-06 a 3x to 9x will perform for most hunting situations. If you are into varmint hunting or long range shots, you can go all the way up to 24x. Now certain manufacturers have BDC type of scopes ( Bullet Drop Compensation) Which takes a lot of the guess work out of hold over for longer range shots. Once set up for the caliber you are using you aim using the built in range compensator dead on and fire.
Also take into consideration what conditions you will be hunting, will it be dense forest, or open plain. If dense forest a lower power scope is best. If open country a higher power scope is best. I prefer variable power scopes so that you can adjust them for the task at hand and gives you more versatility.
Always zero and practice before going into the field, you owe it to yourself and the game you pursue. For smaller caliber rifles a 50 yard zero is what works best for me. For larger calibers I like to be two inches high at 100 yards. When you can consistently can hit what you are aiming at at the range or a controlled shooting area your ready to go hunting.
Good luck and always hunt ethically.
Todd Inman, Owner of Western Outdoor Supply a e-commerce retail web site that sell the finest in Outdoor Gear, Hunting equipment, optics, camping gear, marine electronics and GPS. http://www.westernoutdoorsupply.net