A few comments:
RH will work fine as a firewall, assuming you have some security know-how. OpenBSD is famous for its "secure by default" stance, and so it would be easier for a newbie to set up a secure OpenBSD system (you generally have to make it insecure). It takes me several hours to build a rh system so that I feel it is safe to be on the network, and I've had quite a bit of practice at it.
Tripwire isn't a daemon, its just a normal program. It uses a few key elements to track files such as modification date and time, but more importanly it creates cryptographic hashes of these files and stores the hash for later comparison. If you don't run tripwire on a known-good OS (basically, right after install, before it hits the network) or you don't keep tripwire and its databases off site (its fairly simple for an attacker to modify tripwire or the database to give a false negative) then its about worthless.
For an example of what one of these hashes look like, run the program 'md5sum'. It is very difficult to create a file that will produce the same md5 hash as the original (read: nigh impossible).
If you're going off some of the basic security papers out there, you may be missing a huge part of the picture. Remember, inetd is not the only place that services get started, so if all you did was tweak with inetd.conf, you've got a lot of holes still waiting to be exploited. Always portscan yourself, or at least run netstat to see what ports are open on your system.
Be sure to keep up to date on patches, rpm makes this fairly easy. Just grab all the latest rpms from updates.redhat.com and run 'rpm -Fvh *'. You should compare the md5sum and gpg signature on the file with the one in the rh advisory before you do this, of course... everyone does that, right? Yeah, sure.
At this point, I would consider that system to be compromised. As such, the best thing to do would be to reinstall it, unless you can confirm with absolute certainty that it is still secure. When you do the reinstall, do not bring the system back on to the network until you have confirmed that there are no services running at all, and you have installed the latest patches for those programs you are running. Don't rely on commenting out inetd.conf, also run 'ntsysv' and see what is checked. Most of the items in the list can be turned off without any problems. If you have any questions about what should be running, then feel free to ask here or on any other linux board you feel comfortable on (linuxnewbie.org has been a big help to a lot of people... of course, sensei got fired, or something, so who knows what's going on).
