I've searched all over the place and couldn't find a straight answer.

If for gaming the specs of a game was a minimum spec of 2.2ghz (for example) and i have a duel core 2.0ghz, i thought that it will easy work ( 2x2.0ghz = 4.0ghz) but I've read that the core's don't work as one when playing games, is that true ?

And if it's not true would the 1'st core use the 2'nds core if it isn't powerful enough ?

Any help Or information would be Appreciated.

What game?
Do the specs list any recommended processors like a P4 or an AMD64 of any type?

The thing of it is GHz isn't really an effective measure of processing power anymore, since they're making chips that are far more efficient and do more operations per clock cycle. For example, any Core2 Duo chip clocked at around 2GHz will absolutely smoke a Pentium 4 Northwood 3GHz chip. And that would still be true even if you were dealing with a single-core processor. When the AMD64s first came around they were clocked lower than the comparatively priced P4s, but the AMDs beat them out for performance.

Dual-cores don't work that way. A dual-core processor can't do one task twice as fast, but it can do two things at once. So the only help you'll have of your second core is that it can do background tasks, like managing the anti-virus and firewall, and leave the first core to completely focus on the game.

The exception is multi-threading, a complicated programming technique which basically involves splitting one task up into several smaller tasks, but it has to be done deliberately by the programmer who made the game.

So for gaming would a 3Ghz+ single-processor is better then a duel-core ?

Not necessarily. Usually you will have more than one program running at one time. Dual-core gives you more resources to handle all those processes. Thus, while one processor is handling your game, the other can run all of your background processes. I am basically restating what Mr. Alpha said. Besides, multiple cores appear to be the future of computing.

Ok, Thanks For The help