Hello, I'm new to this so please bare with me.

I believe my homepage has been hijacked. When I enter windows explorer I am automatically redirected to a site called security center. the address is ieprotectpage.com. I tried to change my home page back but to no avail. Also I'm continuously getting pop ups about spyware dowloads such as trojan-spy & spydawn. How do I get my homepage back and get rid of these pop ups?