making a scan disk?

My computer was just infected with some kind of virus last night and I cannot access anything nor can I get online. A friend of mine suggested going to the avast website and burning the free version on a cd as a “scan disk” since I do not currently have Avast on my computer. He said I should be able to insert the cd in my computer then and scan my system for this virus. However, I have been on the Avast website and I’m not sure how to make this disk… can anyone please give me some suggestions?

Thanks so much!

Dr.Web® LiveCD

Emergency System Recovery Disk http://www.freedrweb.com/livecd/?lng=en
How does it work? http://www.freedrweb.com/livecd/how_it_works/

You will have to download and make the CD on a clean computer