I rarely run any level of antialiasing in games due to the performance hit they usually take for me, but I HAVE to have anisotropic filtering set to at least 4x, preferably 8x. Such a massive difference with AF on versus off.
I also tend to be willing to sacrifice shadow details, but like to run a fair bit of lightsources. This all depends on the game though.
The original NWN has always been my benchmark for testing a rig upgrade; how does it run with as much special effects I can throw at it as possible? Anymore, I can max everything on it and it runs just fine. I need a new benchmarking app.