Don't Limp
Can only agree with everyone else, whatever you do dont limp
always remember if you limp you only have one way to win a hand, have the
best hand
If you raise you have two ways of winning the hand, having the best hand or your opponent/s folding
I used to limp a lot when I first started playing and had to force myself to raise and now I raise a lot and although I dont win a fortune I am a winning player (just) in Sit n Go's and MTT's
As someone else said in another reply there are so many different things to consider, stack sizes etc, but if in doubt raise, it is always the better option