Top 5 trad tunes to learn on whistle?

Each session has it’s own vibe. I’ve been to a few like you described and never went back. However,there are a lot of sessions that are very open and welcoming.I go to a wonderful one at The Garryowen Irish Pub in Gettysburg PA. It’s an open session,with some fantastic players and some relative newbies. The person who calls a tune sets the pace and the group is really good about keeping to it.Nobody gripes about playing an old warhorse of a tune. People let each other try out their instruments and people are generally all smiling.Many hang out after the playing to have dinner together. That’s the kind of session you need to find.