Best selection is Gamer's Edge in Stroudsburg (a bit away from Scranton). 2nd would be Evolution Games in Wilkes-Barre (ok selection). 3rd would be Tactical Advantage in Edwardsville. 4th and closest to Scranton is Adventure Games in Dickson City. More of a club than store, but carries some games (a lots of Magic, Warhammer and X-Wing).
If you are in the area frequently, try to make Mepacon, the twice yearly 3-day gaming convention with great games and vendors.