I'll copy-paste from the same post that I made on the Microsoft Help Forums:
My computer was working fine today, and I shut it off properly when I went out to eat. When I came back, however, I was unable to start my computer normally. I was unable to click on anything at all, including the start menu, so I shut it down using the button. Now, I've started up my computer in Safe Mode with Networking, and found via troubleshooter that my problem was "Playing Audio," specifically, "One or more audio service isn't running." The troubleshooter was unable to fix this problem, and I cannot figure out how to do this on my own. I have Windows 7, and would like to know how to fix this so I can watch videos, listen to music, (etc). and get my computer running normally, not in Safe Mode with Networking. Thanks in advance for the help! I guess Music, Photos, and Video is the proper place to put this, put I'm not exactly sure.
I did some searching around, and I think that the audio driver is the problem. I went the recommended route and tried to see if that needed updating, however Windows 7 said that my audio driver was up to date, with the newest and best version. Note: this was in My Devices under "System Devices." The driver I tried to update was "High Definition Audio Controller."
EDIT2: Posted from phone. Tried rebooting computer, and it started in regular mode. Didn't work again. Was going to start computer again in safe mode with networking, but computer started doing a disc check. I don't know what that means. Anyway, after that it started in regular mode again and still didn't work. Trying to start in safe mode with networking again currently.
EDIT3: Okay, back in Safe Mode with Networking. A friend thought it might be the sound card, so I went to Device Manager again, but this time under "Sound, Video, and Game Controllers," and there was no sound card listed. However, there was a thing called "Intel(R) Audio Display." I tried to update that driver, but that turned out to be completely updated as well. I am now thoroughly confused.