Many bike lanes are substandard and dangerous. I only use them if they're safe. MOST places don't require you to ride in the bike lane, but a few do. You should check your local laws so that you can be prepared in case you ever get any flack. Also, keep in mind that most motorists don't undersatnd why you aren't in the bike lane, which can make some of them more irritable than usual, since they assume you're a jerk trying to make a point at their expense. Just let it roll off. I don't let clueless people driving cars tell me how I should be riding my bike.

Take the lane. You're right to do it, it sounds like. There's room to pass you in the other lane, so you're not being inconsiderate. Your saftey trumps anyone else's convenience, anyways. Irritable people who honk at me certainly don't get special treatment. To me, honks mean "I see you", and that's it.

You should get a helmet mirror, though, if you don't have one already. That way the bike lane can be your safety net to dive into if anything bad comes up behind you.