Mac OS Lion freezes too

I realized that the Mac OS freezes too and not for a serious reason. I just tried to install firefox and Finder caused my Laptop to become unusable.

So following the advice in this site I cleaned its preferences but there was no respite.

As a last resort I booted in single user mode and issued rm /var/db/.applesetupdone. I created a new admin. user and deleted my old administrators.

That wasted my Sunday. This has never happened to my Ubuntu desktops.