Call Of Duty
 

So I was doing some looking online, and was wanting to get the first Call Of Duty. I also found an expansion pack. But my question is, what, if an, difference is there in these two, minus the difference in platforms?

Call Of Duty: Legacy

Call Of Duty: Deluxe

Are the two games included in the PS2 version, just ports of the two in the PC version? Or are they four completely different games?