Are the Vienna Woods worth a visit in late October? Best way to do?
Absolutely. Take a local bus and enjoy a visit to a heuriger for dinner. That is what I did several years ago when I traveled in October
Planning to go for heurigen in December (but sitting inside)
Take a local bus (or tram).
heuriger for dinner: make sure it has live music, preferably folk music or, even better, Schrammelmusik
Easiest access is from the Cobenzl and Kahlenberg areas of Vienna which you can reach with bus 38A from Heiligenstadt station or from Grinzing. Other great places to access the woods are from the lovely towns of Mödling and Baden which lie to the south of the city and have easy train connections.
Are you wanting to hike/walk or do something else? Wouldn’t be high on my list for late October. Many on this forum associate the Wienerwald with heurigen, which I don’t really understand.