Generally you get the latest patch only as it will patch any version to the latest, but dont use the incremental ones like the ones in RtCW that say 1.3 -> 1.4. Getting one that just says 1.4 for example is good and that way you dont have to worry about what current version you are using.
I just got v1.32 for Quake III Arena from Gamespot. Those are too much patches for QIII that why I ask. But v1.5 for COD, it won't update when I run it!