No, different OS, different updates. By the way if your Vista is an unattend one and not an untouched one, there is a big chance that the SP2 install fails. Service Packs have protection to prevent them from installing on an modified Vista.
@ Lenmaer, be specific by unattended your really mean a vlite one Yes vlite screws up sp2 installation.
Certain chipsets have a problem with Sp2 and microsoft disable the windows update upgrade on It. I dont remember where i read, but it´s on microsoft KB. Usb Bluetooh devices also has problems too.