Many of you replied in my thread about going to NYC. For those who didn't, I'm excited to say I will be going to NY with my university's choir and singing in Carnegie Hall!

I leave this Thursday, and I couldn't be more excited!!
A few last questions:
1)what to wear. I'm used to Arkansas weather. What's the weather like up there? Also, I'm a big flip flop wearer...is it too cold for flip flops? Will I need my jacket? Here, for the most part, it's been warm enough for just a long sleeve shirt or sometimes a t-shirt. Also, keep in mind that since we're going in a group via an organizaiton, we can only have one piece of check-on luggage on the plane so I have limited space.
2)Me and an SAI sister have tickets for Beauty and the Beast on Saturday evening. What's appropriate to wear for that?
3)Because we can only have one piece of luggage, I have to...eek...FOLD UP my choir dress in my suitcase!

Any tips for minimizing wrinkling?
4)We are staying in the Grand Hyatt above Grand Central Station, and rehearsals are at Church of Our Savior (Park Avenue at 38th St). Where's some good places to eat around that area?
Thanks in advance!!
ETA: location of church