Oh! In the boot loader right?
Well, you were right. With acpi=off, my machine stopped freezing once connected to an unsecure network (still haven't gotten it to connect to my WEP secured network).
I didn't realize that older hardware had problems with acpi, and I have a Compaq Presario 1200 laptop (500Mhz, 128MB). It doesn't get much older than that!
I do get an awful sound out of the speakers now during internet usage (like downloading). But that's a separate question.
Thanks for posting your own replies!