Hi i have kde4 in 11.1 and i have the BIG issue

i want to install a virtual machine software
so i tried virtual box ose (IT WON"T START!)
and i want to install a antivirus
i tried clam (can't see it anywhere!)
i tried Klam (it start but scanning don't work!)
i tried antivir (wont start!)

so i have no choice that i have to use avg **** edition (linux edition)
and i want to install my webcam which is a microdia u-cam and i select the right type of system type mine is (x86-64) and I keep getting error messeges!

why is this happening to me with software and why is it hard to run it and install it?

please help me with this issue please! im bagging you

thank you