cant open programs in control panel

just had the malware virus called xp antimalware managed to get it off by using these 2 websites http://www.2-spyware.com/remove-xp-antimalware.html and http://www.myantispyware.com/2010/03/17/how-to-remove-xp-antimalware-2010/ i downloaded malwarebytes now its working good, except for some new problems now i cant open any program in the control panel i get the message saying C:\WINDOWS\system32\rundll32\.exe "application not found" also files that i choose to open like firefox for example acts weird and i get the message what program do i want to open the browser with

 

Hi and welcome to TSG!

After you run Phantom's fix (and that should do the trick!) please do this so we can be sure you are virus free....

Click here to download HJTInstall.exe

• Save HJTInstall.exe to your desktop.
• Doubleclick on the HJTInstall.exe icon on your desktop.
• By default it will install to C:\Program Files\Trend Micro\HijackThis .
• Click on Install.
• It will create a HijackThis icon on the desktop.
• Once installed, it will launch Hijackthis.
• Click on the Do a system scan and save a logfile button. It will scan and the log should open in notepad.
• Click on "Edit > Select All" then click on "Edit > Copy" to copy the entire contents of the log.
• Come back here to this thread and Paste the log in your next reply.
• DO NOT have Hijackthis fix anything yet. Most of what it finds will be harmless or even required.