I'm using IE6 at work and I have my 17" monitor set up in portrait mode which narrows the page slightly, and 768x1024 resolution to suit my aging eyes, so maybe the problems are due to these idiosyncratic features. Anyway, here are my forum problems:
Some forum features "Wrap around" inappropriately on the page and overlay other items and links...it's not happening now so I can't say when it happens.
When I search for a specific keyword I get a list of threads rather than posts so if it's a multipage thread I still can't find what I'm searching for. This is true even if I specify "posts" in the advanced search feature.
Sometimes the date of each post isn't displayed so I don't know if I'm replying to a recent or ancient post.