Sound Problem

I have a Dell Inspiron 1721 with Windows Vista. When I go to the Control Panel and go into my Sound settings, it says that everything is working properly. There isn't, however, any sounds coming from the speakers. I was trying to set up my Skype microphone and then all my sounds stop working. I tried going through everything I could think of with no progress. Please let me know where to go from here to get my sounds to work and for my microphone to work with Skype.

Make sure you test the following:

1. Make sure your sound card drivers are updated
"Driver Genious Pro"
2. Make sure your plugs from your devices are plugged in the right places in the back of your computer. "I know sounds stupid, though it happens to the best of us"

3. Go into Skype settings and make sure you have hardware options setup right! Iam not a pro at Skype I only know basic functions.