A gig on Fiverr offers to Download an entire website from the Internet Archive Wayback Machine. I’ve put in a test order for the vanished Runtime DNA Forum, as partly archived at late 2015, and I’ll see what he can provide in a .ZIP for $6. You have to specify the capture date and time, he won’t just get all dates from a URL across several years and then put them into a massive mega-bundle. The Wayback Machine shows 100,000 pages archived across 108 sessions with the RDNA Forum.
While it is possible to do what he’s offering for free, the only options are Linux, command-line, or a couple of subscription/paid Cloud services — yuk. There appears to be no Windows freeware solution as yet that has a graphical UI front-end rather than bare command-lines.
Update: Got an archive with 3,000 forum threads, and many more individual posts, which is pretty good.
Update: Community archive of the old Runtime DNA forums at the Internet Archive.