I have never had a problem with the history not recording commands in bash on OS X and that's going to back to least 10.4. What does bash --version reveal? Mine reveals
GNU bash, version 3.2.57(1)-release (x86_64-apple-darwin14)
Copyright (C) 2007 Free Software Foundation, Inc.
What if you try bash from homebrew? It's a newer build.
As to the Mac crashing (should be this its own thread?), how is it crashing, a kernel panic? Spinning ball? Does the system.log say anything? If you have DiskWarrior, you can run that to check the filesystem. Odd things things can happen when HFS+ corrupts, which does happen from time to time, but I don't trust the builtin fsck to fix it.