Is there a way to capture text messages into an image? On the iPhone, if you hold down the Power button + Main button, it'll take an image of what's on the screen.  I've used it in the past to capture and print out text message exchanges.  

Is there a way to do this if the text message exchanges span multiple pages?
Only by scrolling and capturing repeatedly and then assembling in a graphics program. Nothing built into iOS currently does it, and SMS data is completely inaccessible to App Store 3rd party apps (protecting your privacy).