A couple more "camp fire songs", especially for the less-than-expert:
"No Rain" - Blind Melon
"Time of Your Life" - Green Day
Wish You Were Here is a great song, and easy to just chord through if you haven't practiced any of the licks in the intro or anything. It is also a fairly easy song to sing. I view it as a little sad for a campfire song, but that is up to the player

All the licks are right on the G major pentatonic too, so if you have a few minutes to figure them out, they are pretty easy.
"Yesterday" by the Beatles is a song that I learned a simplified version of from a book. I can play it decently on my acoustic, and it sounds great. I have never been able to sing that one decently though.
Mama Mama many worlds I've come since I first left home.