Not able to Install OS

I have been using Windows XP Home Edition.
Processor is 1.7GHz P-III, and Mercury Motherboard with 128MB RAM.

I once formatted the hard disk and wanted to re-install the OS.

But when I tried it, the set up runs till the choice screen , where setups prompts to press Enter to install.. but there on the system stops responding.

I have tried it with another hard disk and got the same trouble.

Is it a Virus in the BIOS or a Boot sector virus.

As I have said everything stops responding after a few minutes from the Power On of the system.

Can anybody help me???