I have seen people coming back and asking what should they test ??
Yes, these are essentially people with less exposure and experience but the fact is that its them who get confused !!
An experienced tester would immediately comment .......EVERYTHING !!
So coming back to the core question what should you test ??
The BlackBox perspective .....
Any sofware would have certain madatory fields and certain non madatory fields on the user interface.
I am not taking any part of usability testing into consideration here .....