Personally, I try to use a static path whenever possible.
Static paths are fine for scripts you use, but if you plan to share the script with someone, it's better to use something like $mircini, $mircdir, or $scriptdir to get to where you want regardless where the person has mIRC installed and how they have it installed and where they put the script.
Btw, "mirc.ini" is actually relative. c:\mirc\mirc.ini is static.
