You will need a visa to visit the usual suspects, AKA Schengen states, you don't need one for Switzerland, (as long as you have the actual card in hand, stamp won't do), as far as the rest of the countries are concerned, isn't it advisable to check their web pages?
Besides I don't think this issue belongs here, you should be posting it in life after GC since we obviously don't know how/what the rules are after GC, not having received our approval.