Hmm...yeah your machine more than meets the requirements.
My first ideas are:
1) Game did not install properly, uninstall and try to re-install.
2) Video drivers are not compatible with the game, although this would generally result in some type of error message, it is worth considering trying other drivers for the 8400.
3) The software may need to be run in compatability mode, as sometimes with newer OS'es older applications that were very OS dependent didn't like to be run on newer OS'es, so right clicking the shortcut and running it in compatability mode for say, windows 2000 or 98 might just do the trick.
4) The shortcut may not work properly so go to the directory where the .exe file is to launch the game, e.g. C:\Program Files\Sim City 3000\SimCity3000.exe (or something like that) and simply launch the executable.
Thats just 4 things that it could be, but sometimes i've seen applications, no matter what i've tried, just wouldn't launch until I re-installed windows clean - hopefully that isn't the case here!
Canon EOS 5DmkII + BG-E6 + Canon EOS 40D + BG-E2N + Canon EOS 33
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