Regular or reg is the name given to a player who plays poker frequently. It usually implies that a player is above average at poker and has some experience with the game. The playerpool is hence often divided broadly into two categories, the regs and the fish (weak recreational players).
The 7-2 Game is a side game in cash games where everyone agrees to pay a player if they successfully bluff with, then show, 7-2 offsuit. If you actually make a hand with 7-2 offsuit and win at showdown or have a bluff called you don't win, but if you can show a bluff you can collect a nice side pot.