Windows 7: Internet seems to be acting funny after problems

First of all I apologize for the horrible title.

Now to get to the problem, not too long ago my internet went down and I had to call the ISP to get it fixed. It ended up being a problem on their end. After they fixed the problem and I reset my router the channel was left on interleaved which made playing online games unpleasant due to the constant lag spikes. I then called them again and had the channel switched back to Fast (which was the original setting).

This is where my problem is right now. I use to be able to run a youtube playlist in the back or grooveshark and play online games. Now I can't do that because as soon as something starts loading the game will start to freeze up and lag.

Thank you for your time.

Are you using wireless .. ?