I have just upgraded my 4 year old PC to run new games such as- gta4, batman arkham city, dirt3, crysis2,etc. My upgraded config. is-
Intel Core2 Duo E6750@2.66GHz
ASUS Nvidia GeForce GTS450,1gb,gddr5
2.5gb RAM(512mb in slot1, 2gb in slot2)DDR2@667MHz x 1RAM
320GB Western Digital SATA HDD
20" Samsung LED(1600x900 res.)
Windows 7 Home Premium 64-bit
The current scores in Windows 7 are-
GPU(Windows Aero and Desktop)-7.5
GPU(Buissiness and Gaming)- 7.6
Hello, your PC looks alright for the resolution that you are playing at. Some games you might have to settle for medium graphics presets or high with post processing turned down. Hard to say how it will do in a year or two from now, but worst case you'll just turn down the graphics quality a little bit.
Another thing, if you're into multiplayer games, some of those tax your CPU rather heavily if the game involves more than 10 players in your view at the same time.
So, to answer your opening question exactly, as of today your PC is ok and will be able to run all the games, but not at maximum graphical settings.