People complaining about games and ice-breakers are such losers. I always look at them and think 'I bet you ****ing iron your socks, you complete shunt'.
Anyway, given that you've got a huge number of people, I'd suggest a pub quiz type scenario. It gets people working in groups, a bit of friendly rivalry and if you do some questions on things people like - film, music, tv, sport and beer, then people will be more engaged. A little prize for the winning team and maybe dunces hats for the losers. Toss in some sweets and sorted!