He might not have a window seat guys.
I suggest something with good replay value even offline. Blockland, Minecraft, Gmod (though the workshop addons will be impossible to disable without digging through the files if you're playing offline and your console will be spammed with steam not rinning errors ignoring achievement progress). Hell you could get Gmod and Fraps and make weird machinima. TF2, CS:S and DoD:S aren't too good for offline play, but will add content to Gmod. HL:S, HL2 (+eps), Portal, and Portal 2 are singleplayer but there's really not much of a reason to play through more than once (HL2 is required for a LOT of Gmod content to work, mind you). L4D and L4D2 are great in singleplayer or multiplayer, with bots having some handy aimboats to make up for other deficiencies inherent to the AI system, like not saving you from that damn smoker for fifteen whole seconds. L4D2 has almost all the content from L4D except updated to include the new stuff, but the AI is worse about being helpful. Beating "No Mercy" on easy mode in L4D is VERY different from doing it on L4D2. I played through all campaigns in both games on easy mode and we didn't get completely wrecked but in L4D2 the AI players never dodge spitter goo till they take damage from it and although they're good at taking out specials before they strike, God help you if a Jockey gets on you in the apartments because they will take twenty-thirty seconds to save you.
