Weird problem with most of Windows 7 menus

[UnTraDe]

My sister's computer started with this problem a while ago. I searched alot and didn't found any solution or something even close to it.
When you're clicking for example right-click with your mouse on the taskbar, it opens a a little menu. In my sister's computer for some reason it opens a huge "menu" on the middle of the screen and you can't see anything, not even what supposed to be on the menu. It happens in a few other places like MSPaint and Skype and etc...
I took a picture with my phone because you cant open anything to post the print-screen on... I hope the image is clear enough:

This is the screen when right-clicking with the mouse on the taskbar:

I'm new at this forum so I hope I didn't do anything wrong in this post.

Thanks in advance! Sorry for my bad english!

 

[iRazer]

Desktop or Laptop?

 

[MedicinalSnacks]

Desktop or Laptop?

By looking at the picture, it is quite clearly a laptop.

 

[iRazer]

Try Checking your Registry for Issues with CCLEANER
and try running a virus scan too.

 

[UnTraDe]

It's a laptop.
I already scanned the computer for viruses and etc... I will try to check for issues regarding the registry with CCleaner though I dont think it's a registry issue.
Thanks for the quick replies!

 

[iRazer]

Oh okay, I hope your problem will be solved.