Virus wont let me start computer.

My brothers computer has somekind of adware on it, but it was pretty harmless until yesterday so i never bothered to remove.

While downloading a file from megaupload one of those fake antivirus advertisements that popped up and downloaded itself to the c drive to my computer and started all kinds of pop ups.
As with all pesky virus's it wouldnt let me start any of my anti malware programs so i deleted them and st arted to repeat the starts to the read me first guide which has helped me many times.

However before installing the programs i figured i would boot up in safe mode first. I Select safemood and it starts going down the list of the .dlls but stops halfway and doesnt continue, i let it sit like this for an hour. I restart and try again nothing.

So then i decide eh why not start it up normally again. When i do this however the screen goes black and then nothing. Is there a way around this.