PC Games on sale for downloads,please help me choose which game to buy?

the games on sale only today at Steam

First of all i'm new to video games i only have Crysis Maximum Edition and COD MW2



1) COD, and, COD 2, COD 4: modern warfare, COD united: offensive, COD World at war. all this for only $30



2) Battlefield: BC2 -alone for $33.49-



3) Civilization IV: $9.99



4) BioShock 2: $14.99



5) grand thert auto IV: $4.99



6) Borderlands: $4.99



7) Killing floor: $4.99



8) Left 4 Dead 2: $9.99



1st: should i pay $30 for the selection of " COD "

OR i pay $33 for only BC2 ?



2nd: is this games are good to buy even if it's a bet old? and which one it will be good to buy?



thanksPC Games on sale for downloads,please help me choose which game to buy?
Um



The cod package would keep you playing a while, also pick up GTA IV since it's a bargain at that price and great fun.



I wouldn't waste 33 dollars just for battlefield.