When it comes to choose the right web server.
I choose the one that you don't mention, the nginx server.
That because it's more easy to compile.
I think also more easy to configure, with one config file.
And you also have test option to test the config file.
But what i think it's the lightest one is the busybox one.
But when i comes to speed I choose the nginx.
That have support for spawn babies (forks it self
), for more connection ready server.