Ocean County Fair is going on right now through the weekend.
Monmouth County Fair is coming up at the end of the month.
Hot Air Balloon Festival in Readington in 2 weeks.
Skydiving at the airport in Wall.
There's quite a few trails for biking or walking at many of the parks around. Holmdel Park and Allaire State Park are really nice. Manasquan Reservoir (actually in Howell) has a great trail that goes all the way around.
I heard Pt Pleasant has a free movie on the beach every Sunday night on the north side of Jenks.