Oh -- final note and need of assistance!

A friend asked me to plan a little get-together for ECE grads after convocation...my questions are.

1. will they be likely to just hang and lunch with their families right after instead?
2. should this be lunch or dinner?
3. i need to get to work the next day so probably no clubbing or wild drinking. would a lounge kind of thing be a good idea? if so, which one? i've never really sampled the nightlife!
4. suggestions on what to do? :D

thanks!