Scout at new system.
Colonize/op a system
Engage Battle.
Recently I enabled EXPANDING HELP
(under game - settings)
I still have some crashes but I have the impression that it helped a lot. (Just played 220 turns and only 1 crash.)
Manual: Expanding Help switches off the expansion animation that some of the windows go through when you open them. This doesn't affect how the windows work, just how they look as they open. Turning this one off could speed things up a little.