pauloaguia:  No, I see now it apparently can't be done.  I was working from memory (having no waiting games) so I couldn't check the screen before posting.  Looks like you can only change the default setting for one of the two boxes, the other by default will always be set for "next game".  I don't find it burdensome to pick a game off the drop-down list, but then I almost always just play them in the order they come up.

However, the left hand menu always includes a link to the Main Page, so I don't see the problem even now.