If you bought the game AFTER June 2005, it is V2, as that is when V2 came out-I bought my game in June 2005, and it was V2...
Here is what the V2 game box looks like..OR at the bottom of the screen load screen, it will say V2.00 if V2...
OR Miromiro's 3rd suggestion about uploading a save to SnP and checking what it says is another good way,,,
But, since you are on Windows 7, I take it you have V2, as I don't think V1 is compatible with newer OS's after XP?