Freerolls are a completely different animal from the tourneys you pay to enter and I play them completely differently.
Regular tourneys I like to see a lot of flops early with speculative hands that are suited or connected. When you hit big you usually get paid, but I generally don't play them out of position or to bets higher than 3BB. They are for speculating, not throwing your chips away against large bets. With big hands like AQ or AK I'll raise, but if facing a raise I won't re-raise, just see the flop. Big pairs are for aggressive play.
Freerolls I tend to play super tight early on, folding just about anything, not even limping, but play high premium hands super aggressive. The 100k's were perfect examples, people would shove with literally any 2 cards so I stayed out of the way unless I had AQ, AK, JJ, QQ, KK, AA then I would be the shover. Even with AA UTG it was automatic, I would get called 95% of the time, often by more than 1 person. It was more of a time invested vs. reward thing, I try to get big early since it takes about 90 minutes to the $ and depending on the time of day it would start at just $0.12- $.30, but if I hit 4000 chips the money was pretty much guaranteed, then it's a matter of working on up the levels. Not until you get down to 100 players does it resemble "regular poker".