You are infected with spyware if:
* You see too much pop-up advertisements.
* Your browser has toolbars that you haven’t installed.
* Your homepage has changed (and you can’t change it back).
* Other settings have changed without your permission.
* Your computer is slow.
To get rid of spyware and keep your computer clean you can use an antispyware or even more.
You can download a antispyware software. There are 10 good anti-spywares.
here is the reviews: http://toptenantispywareviews.com
You can download one and scan your system.
All are safe and can be trusted.

You need to rename the Malwarebytes executable file. Go to Start then Search. Type in
the following in the search box “mbam.exe” Right click and rename the program to
something else like “1mbam.exe” after that reboot your computer, do not just log off
user but totally reboot the computer. When you are back at your desktop go back to
search and search for the new name we gave that file, ie “1mbam.exe” and then double
click on that file. Malwarebytes should run now and clean your system.

rename the exe. in program files because the mallware stops the use of these programs so it can mess with your computer. It works trust me.
so go my computer>Hard disk>Program Files>Mozilla Firefox> look for the file that says .exe on the end and change the name. Click on it download malwarebytes rename the installer. Install it and change the .exe name for that as well.

try superantispyware, it has a fix for a locked system restore