Changing Aspect Ratio

Alright, I have an iMac G5 and I use mirroring on a tv and was wondering if there was anyway to change the aspect ratio of the display. I've went through system preferences and done about everything in there, but I can't find anything about aspect ratio. When I'm using my tv I can't see the very top menu bar or the dock. Any comments would be appreciated.

Thanks for the help.

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MacGuy18

1. The menu bar can only be on one screen. So unless you went into System Preferences>Display>Arrangement and dragged the MenuBar over to the TV it will only display on the default monitor.

2. The dock is the same way, it will ONLY appear on the main monitor, unless you have the arrangement of the TV so that if it's to the left of the main monitor and you keep your dock on the left side, it will be on the FAR left of the TV.

I'm talking about mirroring. Not using the tv as a different display. I can see everything on the desktop and just the top of the dock if I strech it out all the way. Also, is there anyway I can use the tv and turn the imac monitor off?