I grew up on second edition AD&D. I played some first edition, and frankly found most 1st edition add-ons to be highly compatible with 2nd Edition.
However, I'm a huge fan of Ravenloft, Spelljammer, and a variety of other 2nd edition add-ons. How can I convert them to D&D 4 in such a way that they're playable, enjoyable, and not super-high-effort? (Or, for that matter, super-high-cost — i.e. I do not want to pay for dozens of new source books.)
Best Answer
I think the two things you have to do "manually" are monsters and treasure conversion, which will actually probably be more of a "re-imagining" than a conversion. That can be fairly labor intensive, though, and I don't know a way around it. Using the compendium and monster builder can definitely help in tracking down and/or creating equivalent monsters, though. I recently used the monster builder to rebuild myconids from scratch to make them like 1e myconids, and it actually went pretty smoothly.
Although you said you don't want to buy new source books, there is a Ravenloft book coming out for 4e that puts the setting in the Shadowfell.