SWs... made up. ST... made up. You guys might as well be arguing over the outcome of a fist fight between Santa Claus and the Easter Bunny.
The two are very differant and hard to compare. ST *tries* be be somewhat believable. SW doesn't care and is just fantasy. If you want to compare them though...
ST pretty much has the same plot over and over again. It seems like they travel back in time in half the movies. I'm also sick of them winning by reconiguring something or pressing a lot of buttons. ST is boring. SW is so much deeper and exciting.
ST aliens suck, it's always just some guy with some latex comstume piece on his head. SWs has Jabba, Yodo (whatever he is), Jaws, Ewoks, and all kinds of things that arn't approximately human sizes.
Really though, the differance between the two is in personal taste, not it which one is better.