Installing dll files separately isn't necessarily the best thing to do. Like brkkab notes, you should get all game updates and patches, and install them in a proper way = unistall the game, then reinstall. Also, I agree with him that you should reinstall / update your video card drivers. Sound can sometimes cause problems, go to Control Panel\Device Manager and check that you don't have any question marks there.
What I don't really agree with, is disabling your Security programs. If you do that, you should also unplug your Internet connection, since we never know what programs run. Especially playing on-line could be hazardous.
Finally, not a bad idea to make a thorough scan with your AV, and Malwarebytes Pro, use the 30 day free trial. These scans are best done in Safe Mode, press F8 repeatedly after the BIOS post, and start them from there. To check your registry with CCleaner wouldn't harm. Nor to defrag your disk after all this.
And, it's always good to give System specs. Best wishes.