Problem after win7 antivirus removal

Alright guys got a problem I recently got that win7 antispware virus I uses malware bytes to remove it but now it's gone my computer won't do anything won't open any main programmes when I click Internet it brings up folder asking what programme I want to open it with my task manager won't open when I click it i get c:windows\system32\taskmgr.exe application not found It's like this with everything it's like I've lost all my programmes I'm on my phone at the moment because my computer is now useless any ideas what I can do??