I've posted this before but I'm running Xp Pro SP2 and I don't see AFFINITY listed as an option under Start - what works for me is install runfirst.exe in the same path as EQ and put the following in Target:
C:\Path to EQ\EverQuest\RunFirst.exe "eqgame.exe patchme"
with the path to EQ in the Start In field.
You can download RunFirst from
http://www.activeplus.com/Products/RunFirst - it's free.
I use this on multiple PCs and it always works.
Regards,
Mg