For the majority it should be fine, especially web based... On my HP 6005 with an AMD/ATI RS880 (HD4200) my 2 boys play web based games fine and I'm using an "open source" driver.
I would suggest testing on a few games/playing videos to see if the output/display is suitable to your liking. If your asking will the open source driver harm the card and/or PC? No it should not, could there be some features missing as opposed to the vendor's certified - maybe, but these options may go unnoticed..
You can always test the other driver options available or directly from NVIDA's site
http://www.nvidia.com/download/driverResults.aspx/112998/en-usLocator:
http://www.nvidia.com/Download/index.aspx?lang=en-us**NOTE** Before testing and trialing drivers.. I would strongly suggest using SystemBack to make a back up (similar to a Restore point in Windows - but better
) If the update is no better or the change caused an ill effect or you wish to undo and revert back, you can easily use Systemback to restore the previous state.