Stop a user from saving the file.

Hey guys, a few questions this time, any help would be greatly appreciated.

1. Is it possible to stop a user saving a file, but still be able to save the file using macros?

2. Is it possible for, when a spreadsheet is loaded, the view to be set so that a selection takes up the screen no matter what the resolution / screen size of the monitor? If so how would I get the macro to run on launch of the sheet?

3. Is it possible to get a form to pop up on launch of the spreadsheet with a logo and just an ok button to get rid of it?

4. And finally, I have a cell which is populated from a database report, the project name often contains / \ symbols. I need a cell which is a duplicate of this cell however with the / and \ symbols replaced with the - symbol, is this possible as a worksheet function? Or perhaps when a macro is run some kind of find and replace coding?

THANKS for ANY help in advance!