I have totally removed all parts of "Profile Information" within the register area.
Firstly, as dj air mentions above, you need to turn off http friendly error messages so can be directed to each error lines within the ASP files.
These are the files I deleted appropriate lines:
language_file_inc.asp
common.asp
forum_posts.asp
members.asp
pop_up_profile.asp
register.asp
Admin>>database>>wwForum>>tblAuthor (delete appropriate fields but be careful)
I started with the Language_file_inc.asp file 1st taking out certain lines and saving the file then refreashing the forum within the browser.
Keep going until there are no errors and test all the way through your forum.
cheers Ali.