Guinness is good (of course) and I've had a few other stouts that are hit-and-miss and a few that are really great. I typically avoid anything that has any flavoring/crap added anywhere, including the name. So no chocolate stouts or coffee stouts or coffee chocolate stouts or ....
My go to for "oh, you don't think you like stouts?" is this -
Oh so yummy but more than one or two is way too filling. But if you are only going to have one beer with a good steak dinner, etc. then it is perfect.