Red Hat 6 is no longer supported; patches are no longer being created for that system.
Download or purchase Red Hat 7.3 or Red Hat 9.0 (don't bother with 8.0) if you want to stick with Red Hat.
If you attach an unpatched Red Hat 6.x system to a cable modem or DSL line, it will be cracked and completely 0wned in less than two weeks - probably less than 48 hours. It's almost as dangerous as unpatched MS-IIS that way.
Seriously, I think you are wasting your time on the old stuff. If you want a pre-2.4 kernel like Red Hat 6 has there are probably other distributions still using it.
That being said....
I don't know how to configure MySQL but the samba configuration file is in /etc/smb.conf or /etc/samba/smb.conf (depending on your version of samba and compilation options used in your distro). The base version is very heavily commented, read it and/or do a "man smb.conf" command at a text prompt.
Again at a text prompt, you can type "ntsysv" to get a list of services to start at boot time. If you're running Xwindows (GUI mode) you can run Red Hat's "control panel" and look at the runlevel editor to do the same sorts of things.