Yes it's very strange that UDF seems supported by XP and earlier versions of windows and this support was dropped in Vista and later versions.
The only suggestion I've found so far is the KB article which I mentioned, which doesn't of course solve anything for me. So isobuster remains the only viable solution.
So what should I do when I want to write files larger that 2GB on a DVD ? Split them into parts ? Is iso+udf more compatible ? I've actually never used this because I've always though it would be the least compatible option to combine two different formats on one disk.