When I was initially hooking up my G74SX to my TV, I tried both VGA and HDMI connections and had a cable in each. Even though one was not connected to the TV, it was interpreted as a 2nd monitor. The Screen Resolution dialog reported it detected the 2nd monitor and I must choose to disable one. Therefore, I don't believe the GTX 560m is capable of running 2 EXTERNAL monitors simultaneously.
However, I believe @Xraptorx simply wants to run the 17.3" laptop display AND one external monitor at the same time. I've found I can choose different resolutions for the display and external monitor, but since both are natively 1920x1080, I can't determine if you are liimited to that resolution or would have the option to choose a higher resolution if the external monitor supported it. Screen Resolution DOES detect the TV as "VF551XVT" rather than "Generic PnP Monitor" so I think it MAY be possible.
As to be able to run a different game on each monitor, I suppose that depends on the games and how much of a performance hit you're willing to take. For me, I typically run different instances of the Commodities Futures game on both monitors simultaneously without an issue... ;>{)>
G74SX-A1 - stock hardware - BIOS 202 - 2nd Monitor VISIO VF551XVT