Guitar Hero Smash hits not burning

So I downloaded the ISO, unzipped it, tried to burn it onto a virgin DVD with ImgBurn and it didnt allow me to, any ideas why? It was a good DVD, and I made sure it was empty.

You unzipped an ISO?
If the file extension says ISO, then leave it as ISO, don't extract it.
Also, did you check the ISO filesize? It may be a wee little bit too large.
And I have to ask, even though you may not be allowed to answer, but from where did you get it as in which release group?

oh, sorry, that was my bad, it was a .rar file the one I unzipped. ill pm you the page