function ideas....

hai friends....
im going to hyderabad after 3 yrs...and im planning to put one function for my kids..(no occasion)..its like a get to gether...as my relatives and frnds ddnt see my kids from 3yrs..and im not having much time for meet each and every person personally..and there is rough idea of minimum 400-500 ppl attending the party.
so can you people give me some ideas about..
1.closed functional halls in and around rtc xroads
2.theme ideas..
3.food ideas like whethre to give cattering or to make the chef to cook in house like giving raw matierials and they will prepare...
4.retun gift ideas.for parents and kids....

Hi i dont hav much idea abt hyderabad city..
U didnt mention the budget.. but still few ideas..
For kids- U can giv drawing book along with color pencils for smaller kids..
Puzzles like rubik square.. or sudoku for little bigger kids..
For Adults- U can giv the floating lamp which is pretty famous in market now.. Or simple terracotta(not confident abt the spelling!!) gifts like bells or even ganesha or any other small idols...