Yes you can, you don't have to be rooted, but you need a computer with the SDK installed. Once root is obtained, then you can download the app ShootMe and take screen shots that way. Here's how to do it on the computer:
Plug in phone, make sure USB debugging is turned on
Open up the SDK folder
Open up the tools folder
find a program in there called ddms and double click it
select the phone from the list on the left then select Devices from drop down menu and Screen Capture. Sounds like a pain, but it really isn't.