How to bitblt this window

http://img65.imageshack.us/img65/6849/screenshotmc1.jpg

i want to bitblt the full height of the window including the hidden part that appear when scroll down :confused:

I know SnagIt has a Web Page capture option that does this. I believe the way they do it is when the hot-key is pressed:

1. They ask the user to click in the middle of the window. This gives them the hWnd.
2. They do a region capture of the displayed portion of the window.
3. Next the window auto-scrolls a set amount which I'm sure is determined on the size of the window that is displayed.
4. Another capture of the displayed window is accomplished and then combined with the first capture.

Items 3 and 4 continue until the entire window is displayed, captured and knitted together.

There would be lots of calculations required and code to determine not only the hWnd but the scroll values, region values, etc., etc. and of course code to paste all that to a single image.

I'm sure it can be done but I don't believe it's a trivial task.

Thanks Tom,
ill your suggession :)