Not open folder by double click, instead of that vlc media player start... what

What folder are you talking about ?
If it is an application, and something else opens up, I would say you have a registry problem, or possibly your system is infected.

At some point you must have set VLC Media player to open just a bit too many things. Use a restore point and go back to a time before the issue started, if it works. A lot of time Restore Points don't do anything to help.

http://support.microsoft.com/kb/306084

It's also helpfull to say when this started, what you tried already, etc...

After about 4-5 posts people end up saying "well, I re-installed Windows over itself 3 times because I deleted some random files and had 34 viruses and I also spilled Coke on the hard-drive", usually after someone spends an hour researching the issue.

Try uninstalling your Vlc media player to see if that still happen. You can always install it back (from another site then the one you've downloaded before) if things go back to normal.

VLC media player is also free.