TV series. No Contest.
Star Trek 1-6 worked well because we already had the TV series. Had we not had the series, there wouldn't have been much point to them. We were catching up characters of a series that had been cancelled unceremoniously a decade prior.
Star Trek TNG worked better as a series, VS Star Trek Generations, FC, Insurrection, Nemesis.
Star Trek 2009, was a good blockbuster movie that I really enjoyed, but for me, is missing that essence that TOS had.
Star Trek ID, for me at least, was a C- to a D+ movie. I really didn't care or it, and feel it was really just too much of a homage movie to be taken as anything more than that.