Taking screenshots on the old iPhone was a difficult task, requiring you to perform a preference hack then do some tricky moves with buttons just to get a screen grab. But thankfully on your iPhone 3G (and if you've updated to the 2.0 firmware update for an older iPhone), it's so much easier and doesn't require any hacking into your new, pristine toy.
To take a screenshot on an iPhone 2.0 (that's "two dot oh" to you, ma'am), all you have to do is hold down the Home button while pressing the Sleep/Wake button. Your screen will flash and presto, you have a screenshot. You can find your shot in your iPhone's photo app for easy download to iPhoto or Windows photo program. Simple. Like the iPhone itself, no?