Hello rdonnelly,
But you could install eCS with USB mouse and keyboard?
Hmmm, if so, then it may be something else that cause you the problems, my guess from what you say is some kind of IRQ conflict.
With USB only ports (no PS/2 at all and no adapters) then the problem is that you can't press Alt+F1 (at least I couldn't/can't) at bootup as USB ain't loaded at that point.
Your option then is to boot to the installation CD and try to disable (REM) out drivers in config.sys that's suggested in the documentation mentioned by others.
I'd personally try in this order:
Sound
Network
...
Btw, have you switched to the SMP kernel? If so, you shouldn't add the /ACPI /SMP switches unless you want to try that it work or know that it does. You can however use the SMP kernel on a 1 processor system.
//Jan-Erik
Actually, I thought it was going to be posted on the web 
I am having problems with ACPI, I have not used OS\2 since early 2000, I never installed it on a machine that only has USB ports for mouse and keyboard. I am not able to get mouse and keyboard support. There is no info or very vague info on installing ACPI. So I am waiting for tech support to help me. They have not been any real help. I have 1.2R and 2.0 RC5 installed and ready to go. All I got out of my purchase was a glorified screen shot of 1.2R and 2.0 RC5. I have it installed, and I get to boot to the WPS, but I can not do a thing with an input device, other then power the system down and boot back to winblows. I had better get some help soon, or there will be one less OS\2 user out there again.