Firefox Google Redirect Issue

[Asianator]

Greetings,

I have been having issues with my computer lately in regards to searching information with Google. Every time I click on a legitimate site like Wikipedia or dictionary.com I get redirected to weird sites. I tried to follow the eight step procedure, but I can't go beyond step 2. Step 3's direction link to disable real time protection is not working for me. I downloaded Malwarebytes and Highjackthis on my computer but I can't open them. SuperAntiSpyware's download link isn't working at all for me. Firefox says there's an error. I did perform step 2 twice and updated Java for step 6.

Other info: I have Avast 5.0.377 Should I uninstall that and install the suggested avast?

There is also another issue. Randomly, these weird commercial audio can be heard from my computer when I'm not even browsing on the web.

I apologize in advance for the inconvenience. Thank you for your help ;_; I'm quite computer-retarded when it comes to viruses and malwares.

 

[Bobbye]

Please tell me what 'real time' protection you are trying to disable. There is some confusion about this issue when running the first three programs.

Firefox says there's an error.

I need to know what the error message is and exactly what you are trying to do when you get it.

What happens when you try to open Malwarebytes or run HijackThis?

The link HERE should work for Superantispyware. If it does not, I need to know what happens when you click on it.

What is your operating system please- Windows XP? Vista? Windows 7? Other?