Yup capture the entire page.

Two useful things i use it for.

#1 viewing the entire page so i can gauge the eye flow of a page and relevency as you move down. great for showing people how there relevance eye tracking is off.

#2 printing the whole screen so i can chop and move parts around to see what works best. That's a lot more efficient for page and project planning, why code it all to see what it looks like when you can do it ahead of time in PS. then get two finals and split test them.