Did you use the updater, or full install?
The updater is horrible.
Slow, unstable.
I went BACK from 9.1 to 9.04, which I'm using now, cause 9.1 was, IMO, a step backwards.
Install the latest version of CarbonLib (http://asu.info.apple.com) and that may fix some things.
I suggest you go back to 9.04 though, personally...