I'd 2nd the bowline - very useful knot. I was once forced to learn to tie a bowline behind my back - seemed fairly useless at the time, but then a few months ago I had to tie something onto the back of the wetsuit that I was wearing - to my amazement I did it first time - muscle memory is an amazing thing.
Eskimo bowline is non-exploding, nevertheless I wouldn't use bowline (or eskimo bowline) while rock climbing without somehow securing the working end.
Kalmyk loop (which is exploding variant of eskimo bowline) is probably not secure enough for rock climbing, but better than bowline for other tasks. Less likely to spill and easier to untie.
In climbing, a great property to have is to be able to identify if a knot is tied correctly by just glancing at it. Figure-8 is obvious. A double bowline is fairly easy. Not so sure about other knots...
I also 2nd the truckers' hitch.
And remember: if you can't tie knots, tie lots