First, I'm not sure the whole watching the movie angle is one that would work. I mean, I know lots of women who thought Capt. Kirk was masculine and all, doesn't mean they would want me to wear around that yellow star trek shirt. Not to mention the argument, "but it's just a movie and the kilt is a costume".

The argument of respect is a good one. Of course you want to respect her wishes, but that goes both ways as well. Talk with her about it, using the "me" argument and not "you". Let her know that it's something you enjoy, and that you are comfortable, and your daughter thinks well enough to get it for you. And it's also valid that you don't tell her what to wear and not to wear (I assume), ask her kindly how she would feel if you said she couldn't wear pants.

And lastly, maybe some of the advice on "going without her' can be good. Not in a mean way, but maybe go somewhere by yourself first to build your own confidence, and to prepare for what might come your way. Kilts seem to be a fabric confidence-booster for us guys, and chances are she'll notice that. That might give her a different outlook on the whole thing too...