Have to admit I'm a bit of a Trekkie, but find it hard to say which is the better. Star Trek is at "its best" as a TV series, the films are shocking, apart from maybe 2 (wrath of Khan) and First Contact.
Trek was certainly a pioneer in sci-fi genre on television, as Star wars was on the big screen.
For me I liked the ethos of Star Trek, particuarly The Next Gen amd DS9.
The different and wide variation of story lines made it interesting, though there is the odd crap episode
Star Wars is more of a good old fashioned good vs evil scenario, but throws in all sorts of undercurrents and comparisons to historical events ie: religion, spiritulialism, genocide, philosophy, politics etc