Ubuntu, Fedora.. ah... wut the heck..

I tried to install Ubuntu 7.04 few days ago, and kept getting the message of following.

There was an error starting the GNOME settings Daemon.

Some things, such as themes, sounds, or background settingsmay not work correctly.

The last error message was
Did not receive a reply. Possible causes include the remote application and not send a reply. the message bus security policy blocked the reply. the reply timeout expired, or the network connection was broker.

GNOME will still try to restart the settings Daemon next time you log in.

After the error message, the screen and the cursor seem to freeze... can't do anything after that.. darn ! .. then I tried to dl and installed Fedora today, and found out the downloaded DVD iso is not bootable?! .. I think I am cursed...

ps. if someone knows the solution for the error.. please teach me how to fix it. I am fairly new to Linux...thx millions !