It's not a mmo, but League of Legends is always a fun multiplayer pvp game. I have some friends playing Spiral Knights and I've wanted to start that up. Both are free to play
HON and DOTA are also an option I guess, neither is an actual MMORPG, but still pretty fun to play. Although they might be hard to understand for some at first.
Used to play one called "Lunia" pretty interesting characted designs, items, skill set, etc... but after a few years it got crappier and crappier due to the whole "PAY to enjoy AMAZING EXTRA FEATURES!!!!" which is basically 7 out of 10 character classes and strongest skills/spells . The graphics are cell shading which is kinda cool (Tenkaichi budokai style) and you can manage to pull a few combos with a little bit of skill combining hits and skills/spells. Ragnarok does have some pretty sucky drop rates from what I've seen and heard, but offers a wide variety of classes. Dungeons and Dragons blocks some clases/races as well. Most mmorpg's are very demanding/consuming on time sadly... eventually I always end up getting bored.