When I wake my brand new iMac from sleep, I get a blank blue screen for 2 seconds before os x actually shows up. Is this normal? The reason I ask is that on my MacBook Pro (core 2 duo, pre santa rosa), it is virtually instant - no blank screen.
Yes, that is normal. It usually takes that few seconds time to wake HD and recover your desktop and open programs on screen. If you have alot different programs and documents open when you put your computer to sleep it will take more time to wake up.