I'm 99% certain the reason MMJB isn't working is because the MS Java Virtual Machine (MSJVM; JVM) is missing. But riddle me this Batman...

Why is it that the version of XP I have on my desktop is the exact same version I have on my laptop, yet my laptop has the MSJVM and my desktop does not?

I went thru the "Add & Remove Windows Components" and there was no selection for JVM.

Can anyone solve this riddle?

Microsoft didn't ship XP with java. I suspect your laptop has XP SP1. This does have java.

Either install service pack 1 or if you search in this forum you will find a link to download MSJVM.