As for getting one of the latest built revisions, check the FAQ on this section and follow
the links on this thread to various sites that host compiled revisions.
A list of the latest changes in source code can be found
here : these can improve or break things or both, so you should test different revisions.
Unless you have a lot of questions to ask, I suggest you try taking the time to enable/disable most of the options in Dolphin so you understand what they do and with how much speed (disabling EFB reads make emulation a bit faster for example)...
