Here is the full list of all 33 YOU DON'T KNOW JACK achievements.
Achieve highest gamer rating
Achieve second-highest rating
Achieve third-highest rating achievement
Get all 7 Jack Attack questions correct without messing up in a 2-player game
Get every question right in an episode
Play 5 hours without getting a single achievement
Ace a DisOrDat in under 10 seconds
Get a multiple choice question right in the last 1 second
Get 10 history questions correct (excluding DLC)
Laugh at a an easy joke
Earn $100000 lifetime
Finish 5 single-player games on Friday or Saturday nights
Choose wrong answer within the first 3 seconds 10 times
Answer all 7 DisOrDat items correctly
Come from behind to win during the Jack Attack in a 2-player game
Listen to all commercials after one episode
Score at least $30,000 over your average
Complete DisOrDat in 30 seconds
Finish an episode
Screw someone for the first time
Get a multiple choice question right in the first 2 seconds
Play Episodes 1-73
Get -$1 million on a Jack Attack
Play Episodes 1-36
Play Episodes 1-37
Win all prizes in Episodes 1-73
Play on July 4th instead of celebrating America
Earn $500000 lifetime
Earn $1000000 lifetime
Get 10 movie questions correct (excluding DLC)
Get 10 food questions correct (excluding DLC)
Get 10 animal questions correct (excluding DLC)
Find the very important gauntlet of fire