Mat, the first thing you should try, as soul_crusher mentioned, is remove support for apm and acpi from your kernel. To do this, you will have to download the vanilla sources from kernel.org. After extracting the file, goto /usr/src/linux and run 'make menuconfig'. This will allow you to configure your kernel, in particular, remove support for acpi and apm. After configuring your kernel, you would run:
Then copy the new kernel, bzImage, to your boot directory and run:
This will allow you to boot your new kernel. Now, I kept this brief and *very* generalized, because you will have to do a significant amount of research on your own. Configuring a kernel is not difficult, it may seem daunting at first, but thoroughly read the documentation provided by kernel.org, and check out the HOWTO's at tldp.org.
When you are able to configure a kernel that boots properly, and have acpi disabled... it should hopefully work (at least it did in my case.. i had the exact same problem).
Good luck, and don't give up. It will come !!!