This guide will show you how to make a copy of this forum or any other. This will only apply to the publicly viewable parts of the site. (To wit, anything that can be viewed without an account.)

You can make copies of whatever you aim HTTrack at. This could be any Web site. This guide focuses on this forum.

First, download HTTrack from its Web site.

The most efficient part to copy is the Web archive of the forum, so that's what the commands will refer to.

HTTrack has both a graphical and command line variants. You can use either one.

For the command line interface, the command to issue is:

httrack "" -O /your-path-where-you-want-the/archive/ "+*" -v -#L99999999
Here's the breakdown:
"httrack" is the program.
"" is the address at which the program should begin.
"-O /your-path-where-you-want-the/archive/" tells the program to save its copy of the forum to this location. You could use C:\Users\John\dpforum\ instead of /your-path-where-you-want-the/archive/ for example.
"+*" means "only download files from within this folder and don't start downloading everything the forum links to.
"-v" tells the program to be verbose when outputting text telling you what the program is doing.
"-#L99999999" tells the program to fetch lots of threads/posts/files and to not stop after 20,000 files.

You can find more information on using HTTrack in its manual.