Ive played lax before but track looks like so much fun
Well look at it this way:
1) everyone participates in track meets so you will get to perform, while not everyone plays in a lacrosse game so if your teammates are better then you might not get much time in.
2) track is running, there is enough running in lacrosse.(unless your doing hurdles or something like that.)
3) do you know more people in track or lacrosse(are you trying to stay with friends or trying to make new ones?)
Track! Try somethin new! But just do whatever you think will be most fun:)
I say track