Gateway laptop stuck on Black Screen. Keyboard not working, DVD

Hello,

Aggravated... last evening just before closing computer, screen popped up and said 'in violation with US code... enter money pack code, etc... (a
Malware virus and scam). Now when I try to boot up, have black screen
And cannot use dvd to recover, etc. I have an external keyboard connected but it has no FN key. I did the remove battery, adapter, press power o button 30 sec, all of those suggestions listed and now ready to give up.