Can’t format machine because of a virus or a hardware failure?

Hello guys. I need to reformat my laptop because of a virus. Now here’s the thing. I’m using windows vista home premium. I had already changed the boot sequence, but it won’t boot from cd-rom.
It brings me to this part (see picture below) and restart after that part. Any help?

Error:
Windows Error Recovery
Windows failed to start. A recent hardware or software change might be the
cause.
If Windows files have been damaged or configured incorrectly, Startup Repair
can help diagnose and fix the problem. If power was interrupted during
startup, choose Start Windows Normally.
(Use the arrow keys to highlight your choice.)
Launch Startup Repair (recommended)
Start Windows Normally
Description: Fix problems that are preventing Windows from starting
