Could not install softwares on my PC

I have a very serious problem here.
I bought a computer just yesterday.
And i am about to install a MS Office 2010, when i inserted the cd onto the cd rom it reject, i tried another installer which is a game installer it rejected again.
And when i tried and search for a free software installer thru the net the installation set up could not be open.
My computer is new and obviously there's no defect on it.
Tell me, why is it that my computer cannot install software?
How can i find the problem so that i will be the one to fix it. Do you have any idea about this problem?
Help thanks
