I believe the "Talking Desktop" to which you are referring is a totally different program from
Zabaware's UltraHal Assistant.
Check to see if you have it in your system somewhere as it doesn't fit the description of
Hal's installer program.
It could be that you might have some other issues of concern so first off, I'd recommend a
full virus / malware / trojan / rootkit scan of your entire system.
Do a cold boot or shut down completely then boot up.
Once UltraHal Assistant is installed you should not see the installer again.
You mentioned configuring things so they do not start again. There are a couple of methods
but while being careful I'd suggest clicking on START > RUN (or if Win 7 type into the blank box,
services.msc
This is a far better method instead of using msconfig and gives the user more control and a broader
idea of what's actually running or being called at startup.
Again, exercise caution before wildly shutting down programs.
Good luck.