How to recover from terminal custom setup

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http://askubuntu.com – I installed ubuntu 12.04 and I added "Terminal" to the launcher bar, the default size of the terminal is a bit small, after some googling here is how I made the disaster change: 1. At HUD menu, type "preference" and I see the option of "Edit > preference", this is as I expected After I clicked the option, I forget the exact steps, but somehow I came to some configuration panel and there is a checkbox for terminal "custom" and I checked it now an input box is enabled and I type "gnome-terminal --geometry 160x50" Now the problem comes, whenever I click the terminal button at the launcher bar (HowTos)