After the patch on 1-31-07, i had the same type of crash to desktop problems. Causes were:
hitting "j" to open quest journal, or using the EQ2 button to open it,
killing a mob that would give a quest update,
examining an item that would give a quest update,
and lastly, zoning would also immediately crash to desktop.
ahh, good times! After much well intentioned advice from ingame players and a guide, i heeded the advice and first deleted my eq2map ui, with no change. Then i deleted the default ui (yes, the whole 180mb folder) and then had to redownload it (which it does automatically when you try to log in and does a file check), also with no success, same crashes. The guide, though friendly and trying to be helpful ended up having me do that basicly twice. Since that didn't work, i tried the advice from the post here to play an unbugged character ... also no help, i even started a quest and finished a quest on 2 different unbugged characters and still couldn't play my main.
In the end, the thing that was 100% successful was quite simply deleting the file in the EverQuest II folder that is titled:
(server name)_(character name)_eq2_uisettings.ini
There are several files that follow that format, but i only erased the uisettings one and zero crashes since then, with eqiimap running as well
Game on!