If you have an opportunity to get all in with AA, KK, QQ, AK, or AQ in a tournament, go ahead. But don't go all in immediately, you lose too much value that way. Depending on against whom you are playing, you may want to increase that range down to 99 and A10; that's up to you to decide based on what you've seen of their ranges.
In a cash game as stacks are deeper you probably should take AQ off that list just because people aren't going to stack with anything you beat. Cash games aren't about risk - they are about expected value
. Don't worry about losing with AQ to K5, in the long run if you use bankroll management you'll be fine.