I guess that depends on what your target audience is going to be. If you wanna play for a bar crowd then I would learn all the old stand-by rock songs. Like CCR, Steve Miller, etc. Throw in some newer songs (red hot chili peppers, nickelback, etc.) mixed with some oldies (Beatles, All Green, Richie Valens, etc.). You get a 4 hour set together and you'll easily make $200 - $500 per night if you're good.
If you just wanna play for fun, then just play what you want. It really depends on where you want to go with your band.
GOOD LUCK!