MattBrancher,
The greetings you refer to reside in the "hello1.brn" file. The only practical way to disable it would be to edit the brain script slightly. I don't know how familiar you are with Hal's brain. The part that has to change depends on which brain you use and which version.
Before you attempt any brain edit, back up the brain file before editing.
If you search for the following code fragment in Hal's brain you will find the section that needs editing.
LetterChoice = "A"
This script fragment is in the Hal Brain that you are using. The original brain is the "hal5.uhp" file in Hal's "Ultra Hal Assistant 5" directory. I don't know which brain you have selected. The brain files can be edited with Hal's built in Brain Editor. Assuming you are using the original brain, go to the Main menu select "Brain Editor", select "Load Existing Project", "hal5.uhp <Ultra Hal 5.0 Default Brain>". Press Ctrl+F and search for "LetterChoice = "A"" to find the right section. I can't tell you what to edit from that point without knowing the brain version you are using.
If you are a little familiar with programming you should see how you can replace the "Rnd" function with a number to prevent the LetterChoice A or B from being selected.
Any questions, just check back here.
=vonsmith=