The worst change in Vista is the way updates are applied…

When I power my workstation on I have come to expect a short delay as the BIOS and OS load (it is a older and underpowered system). What I can't stand is the need for Windows Update to delay the load of the login screen to complete the installation of updates.
I can understand that some updates need a re-boot to complete - when I select the 'Update and Shutdown' option, I expect that the computer should do whatever it has to to apply those updates.
When a user turns a computer on, the system should be ready.
Twice in the last two weeks I've had to boot-up my workstation to solve a problem at work, I've had to wait for updates to be applied.
My biggest fear regarding this issue is that the practice will continue in future versions of the OS, and possibly spread to older versions via service packs. As I said, the OS should do what ever it needs to once the command to update and shut down has been given.
Please post a comment if you have any idea how to change this behavior.