[AccessD] Locking Up a Form

Hey All
What tricks do you employ to restrict a user to use your navigation 
buttons on a single form and also to prevent them from crashing a single 
form???
Just wondering because there are so many exotic combinations and kind of 
hard to catch all.
I have the general stuff 
PGUp,PGDown, UpArrow and DownArrow disabled
Ctrl F (sometimes P) and Ctrl F10 disabled
Transparent buttons
No mouse scroll
Return to the Main Menu to close the application, can't use the Close 
(X) button on the app. window. 
Use Access Special Keys disabled

Thanks