There is a default my.cnf that comes with mysql (4+5) that will make mysql run a bit quicker if you have 2+ gig of ram
cp -f /usr/share/mysql/my-huge.cnf /etc/my.cnf
There is also my-large.cnf, or my-medium.cnf depending on your hardware setup. Check the contents of these my*.cnf files for the one that's right for you.