Can't seem to boot Win7 DVD

I recently somehow got a nasty virus into my lappy. It was extremely weird since I just bought a new anti-virus (Norton, to be exact) and my PC became super slow. I recognized signs of viruses and I decided to wipe the PC clean. My friend gave two Windows 7 DVDs. However, even after making DVD the first boot order at BIOS it just doesn't work. My DVD rom makes really nasty sounds and it waits on a black screen for a bit and then it shows me to choose safe mode or start normally. Basically, my PC has always read DVDs (logo on it confirms it). Also, Rom itself isn't broken, other discs like the Norton one work fine. Since the DVDs my friend gave me were DVD R- and DVD RW. Later, I got yet another disc which was DVD R+ but it STILL didn't work.

My PC doesn't recognize the DVDs even normally, through My Computer.

So, I'm lost at what should I do.   Did the viruses ruin my drivers or something? My rom always read DVDs but why make weird noises now?

Thanks. I'm new here, please don't be harsh