Rookie in need of TECHNICAL help

[nerfherder]

I need a little help and am hoping someone who has some experience can tutor/school me on this. I have a boot disk, and although 26 years old am happy to say I did it myself. Now I am lost. As per the directive I am not going to ask where to find games, I have already found them. Now I am looking to find out the following:

1- What are NFO and SFV files?? Do I download both??
2- After download I use WinRar?? And if so what files do I then put on disk??

Like I said I am in need of a little help. I am NOT looking for game addresses just a little technical assistance. Even posting a website with the instructions would be a great help!! Especially for any other rookies out there in my shoes.