Getting Involved with JJ
More often than not, you will want to raise this hand pre-flop. The idea being that you want to take control of the pot, but at the same time you want to keep the pot small. So don't over bet pre-flop.
Your goal with jacks, in a full-ring cash game, should never be to get it all-in unimproved. Wait for a set or an open ended straight draw with top pair to shove. You want to keep the pots small, you want to check and call at certain points during the hand, rather than betting and raising at every opportunity.
Unfortunately it's not always apparent whether you have the best hand or not going to the flop. However, most times you will be ahead. Jacks are simply one pair though, with three ranks of cards higher than them. So even as an overpair, jacks are still classified as a "small pot hand." Your best bet with unimproved jacks is to control the pot - keep it small and manageable.
Best of Luck!
"The Roving Rounder"