Do it especially if you wear tight pants off the hill
but if you don't have the ski style to go with it you might look a little funny at first. (like if you're still trying to be thug)
I wear Airblaster or taken in northface pants when I ride and it definitely makes you stand out in a crowd.
as for taking them in I know there's a thread on NS somewhere that shows you how to do it
But if you can't find it PM me and ill help you out.