I bought a new PC yesterday, set it up today. I don't have a windows boot disk at the moment, so I plugged in my old hard drive from the previous computer. The computer won't boot correctly - It recognises the drive, and can get to the 'Loading windows' screen, but then a very very brief bluescreen occurs, and it goes into repair mode. It announces that it's repairing HDD files, then reboots, and the same occurs.

Does anyone know what could be happening, why this may be?

(Not sure if this is relevant, but I haven't installed the mobo drivers, GPU drivers, etc.)