It is important that you get update as soon as possible, some update are related to security and in order to be apply you must restart your PC and Windows will ask you to do that. In Windows when update been installed, if it ask for restart it will shows a message and ask you to restart now or later. In Windows Vista and Windows 7 you could postpone it up to 4 hours and if you don't give any response system would restart automatically after 10 minutes. Windows will always warn you before restart by default.
While that may be true, it is ABSOLUTELY not neccessary for the darn program to not even let the user hit cntrl S and exit the program they are using!!!