The process for changing your administrative e-mail address at PayPal is quite tricky for some reason. Also you won't find anything on their far from helpful 'help' page. So here, for mine and possibly your benefit, is the instructions.
Login to PayPal
Go to Profile > Multi-User Access
Add a dummy user (we'll delete it shortly)
Once you have dummy user you can see link to change admin address.
Do that and then delete the dummy user