ok i only know half of what you asked for... my firewall is McAfee. Connection type is cable. The model # is DHP. I dont know what is a OS version, ram, or what a router is. I dont know how to check my HDD availability. I have a Dell Intel Pentium 4 with windows XP. so if you could, tell me how i can find out that information for you. Incase you havent noticed I am not good with computers. So forgive me.