ST-V, hands down is my vote as the worst ST film ever made. "Insurrection" is a close second. I nearly walked out of the theater on both movies. I have not watched either movie since for all the reasons already stated in previous posts. "The Wrath of Khan" is still my favorite by far.
I would also recomend that you do not start any further into the series then season two. Otherwise you miss a lot of character development. I just finished watching the last episode of season three. I already have season four reserved. I can't wait. I know DS9 has it's detractors but apart from TNG, it's the best ST series out there in my opinion.