my 1st dvd burn on my mac mini

[Jude DaShiell]

I got an iso image downloaded and got a dvd blank which is a -r format. 
Could have gotten +r but that's a newer format and I don't know that the 
mac mini would support it for sure.  So I select the iso and make a new 
burn folder called burn folder.  Then I command-c the iso file and select 
and open the burn folder then I command-v and the iso gets copied into the 
burn folder.  Earlier burn disk was shadowed.  Do I close the burn folder 
and select it and then select burn disk?  The dvd blank I put in was 
ejected earlier.