I played for an hour or so and everything was fine, but all of a sudden the time per turn started increasing to the point of making it not worth playing, is this a bug? or is there just so many units/countries that my PC cant handle it?

:(

Lag time will increase for a while due to the massive amount of units in play, however, once the AI starts to loss units by the bucket load then the time should improve again.

You'll find that between end of '39 till sometime in '42 the game will really slow down. The amount of troop movements by the AI.

hmmm so my 2.4ghz computa cant handle it eh?

i was playing 1939 version, historical - do you think any other version, perhaps pacific would be better to solve this problem? or just upgrade my computa?

Pacific is very much less CPU intensive. The lack of Bitter Winter means the massive slowdown for it doesn't occur. :)