Finally I got a method on how to get back my IE6. It is quite simple actually, Without formatting your machine.
All you need to do is go to your control panel:
Start Menu -> Control Panel -> Add/Remove Programs
Select Microsoft Internet Explorer 7 . Then click Remove.
Restart your pc and you can use back your IE6..! Now you are done. Easy, right?
Hope this will help.
[Thanks wmafendi ]