Will this PC play Far Cry 2 At Highest settings 256mb nVidia 8800GT graphics card Processor is ok 4gb of 660MHz Kingston ram can this PC play Far Cry 2 with highest settings

Will it run at highest settings? Yes
Will it run at playable frame rates? Maybe

The ram is fine but the graphics card is only decent. Also, giving the processor will help, even though you said it's OK. If it's a dual core or quad core, then it should be fine but a single core may also hold you back.

It is usually said that 30FPS is the minimum you want for any first person shooter like far cry but your system will probably just make that. If so, then you may want to turn down some setting from their highest like resolution, anti-aliasing (AA) and Antiscopic filtering (AF).