Here is the full list of all 37 Call of Duty 4: Modern Warfare achievements worth 1,000 gamerscore.
Complete 'All Ghillied Up' and 'One Shot, One Kill' on Veteran difficulty
Find 15 enemy intel items
Complete 'Safehouse' on Veteran difficulty
Complete 'Shock and Awe' on Veteran difficulty
Complete 'The Bog' and 'War Pig' on Veteran difficulty
Complete 'Hunted' and 'Death From Above' on Veteran difficulty
Save the farmer
Complete 'Charlie Don't Surf' on Veteran difficulty
Complete 'Blackout' on Veteran difficulty
Complete 'Crew Expendable' on Veteran difficulty
Complete the cargo ship mockup in less than 20 seconds
Complete the game on any difficulty
Corner Zakhaev's Son
Carry Cpt. MacMillian to safety
Complete 'All Ghillied Up' without alerting any enemies
Find Al-Asad's safehouse
Kill 3 enemies in a row with your knife in the single player campaign
Operate an AC-130 gun ship
Kill 5 enemies with one shot while in the AC-130 gunship
Kill 2 enemies by blowing up a car in the single player campaign
Stab an injured crawling enemy
Survive a dog attack
Kill 4 enemies in a row with headshots in the single player campaign
Protect 'War Pig', the Abrams tank
Save Pvt. Roycewicz on the stairs
Kill an enemy while blinded by a flashbang in the single player campaign
Kill the power
Infiltrate a cargo ship
Complete 'F.N.G.'
Find 30 enemy intel items
Destroy all the TVs showing Al-Asad's speech
Sky dive to safety on Veteran difficulty
Complete the game on Hardened or Veteran difficulty
Complete 'Heat' and 'The Sins of the Father' on Veteran difficulty
Complete 'Ultimatum', 'All In', and 'No Fighting in the War Room' on Veteran difficulty
Complete 'Game Over' on Veteran difficulty
Shoot down an enemy helicopter with an RPG in the single player campaign