I haven't tried this, because I've been using Tomcat myself for years and never really had any trouble installing it. Besides, I've recently moved on to JBoss. I just wanted to make a few gratuitous suggestions. :-)
First of all, the Web site doesn't give enough information about what the installer installs.
I see you've added Ant, which some might find useful, but not me. I use Eclipse, so I don't need to worry about Ant. Is this component optional? If not, it really should be.
Do you install mod_jk? This would be a big help for people who want to use Tomcat with Apache. If so, how do you deal with modifying httpd.conf? Is this scripted, or do you just have a readme that says "paste this into your httpd.conf file"?
Do you include any sample apps to test database installations and demonstrate how to connect? I think this would be really useful. I know there are a lot of options available, but just covering MySQL and PostgreSQL on localhost would probably satisfy at least 80% of your audience.
You might also want to consider writing an installer or setup script for JBoss. Having just installed it myself and going up the learning curve to get my first couple of J2EE apps running, I think you could save people a lot of time and trouble.
On the other hand, I sometimes wonder if people who can't figure these things out for themselves have any business running servers on their Macs. I'm torn between the idea of making things easier for those people and simply trying to educate them about how to do things for themselves.