Here s a couple - might be a bit pricy but I would bet both have a lot of experience with the kind of party you want to have:http://waynehotel.com/http://www.radnorhotel.com/Both are in the geography you are looking for.
the inn at penn is good place to hold a party the food is good and they have a good dance floor. is in the heart of univ. of penn at 3600 samson.215-222-2000 i think
You may want to try the King of Prussia area. The Adam s Mark hotel may just be the place.