On to the point all the wizards have a file called Default.js, usually located in
"C:\progra~1\Microsoft Visual Studio .NET 2003\VC#\VC#Wizards\CSharpEXEWiz\Scripts\1033"
(Note:The language name and directory of the wizards not withstanding, and the wizard you want to modify.)
Inside this file you will find a function named "GetTargetName" or some variation depending on the language. Inside this file is the hard coded value "Form1". Here you can change it to whatever you want, myself I have frmMain, but it is a matter of personal preference I think.