I'll play just about anything, so all of the above, plus Stratovox :P
That said, I never really liked the look or play style of Galaxian/Galaga...eh. Played it a little recently, too. I go for stuff that has better control and more frenzied action - games with powerup shots are great! Big fan of Capcom's 1941 here. I've got at least a dozen shooters to try out with the x68K I got recently, so I'll have to see how those are as well.