Most MMO's will have a wiki somewhere, and if they are any good there will be a page with all the lingo spelled out for ya. If that fails, well there's always asking about what specific lingo doesn't make sense to you and we can try to pretend it does long enough to tell it to you. City of Heroes came out free the other day, and I'd say that one has a simple enough system that you can get used to MMO's from it and work your way from there.
Dear gosh, I knew the wii had shovelware issues, but I didn't realize most of it was coming from the same freaking company. I just figured they were from a bunch of no name companies throwing their student thesis project onto shelves. And it turns out that it's an entire company that specializes in just that.
I work at a christian bookstore that recently merged with a publisher over in the UK. I tend to refer to them as brits all the time, and they've refered to us as yanks before in conversations, and nobody's really cared really. In the northeastern area, so really the only way that's going to offend anyone is if they're a red sox fan or something.
I mean, goodness knows I make enough tea jokes with the brits when we have them over. And hey, they get to joke about portion sizes at restraunts in america. A good part of it might be we know we're just having friendly jabs at each other, so I guess it simply depends on the context. But at least in casual conversation, I'm not going to care much.
They'll run out of games to add to the service eventually, but I doubt the service will up and close anytime soon. If I ever get around to getting a classic controller, I'll probably get a couple games from there myself that I never got a chance to play, like starfox 64.