How to take a single screenshot of a large folder's contents in Windows
Solution 1:
The free version of FastStone Capture will do this.
Use the 'Capture Scrolling Window' function (which also works on web pages):
Solution 2:
As per the earlier comment, you don't say why you're doing this, but by far the easiest way to do this would just be to capture the output of a directory listing at the command prompt. This also has the advantage over a screenshot that if you want to do anything with the listing other than just look at it, you can easily import this listing into other apps (eg Excel) or run scripts on it.
All you'd need to do is run CMD
change to the directory you want to take a listing of and then run something like:
dir /B > c:\temp\listing.txt
This would give you a list of all the files and folders, with no headings, or file sizes etc, saved to a file called listing.txt in c:\temp.
Alternatively if you want all the extra info then this might be better:
dir /OGN /W > c:\temp\listing.txt
Solution 3:
A few Screen capture tools allow for you to define scrollable regions for screenshot composition.
FastStone Capture or SnagIt which are shareware possibilities. Or EasyCapture, a freeware alternative