I have a MacBoo from 07 with Tiger installed on it. I went to install Snow Leopard the other day and encountered a problem. I later learned you cannot do this. So I went to reinstall Tiger, but when it prompted me to selected a location to install it (Macintosh HD should have been my option) nothing was there - there was nothing to select so cannot get beyond this page.

Has anyone encountered this? Or know what to do next?