dalek - ACPI/APIC are not your problems (Well, not your AGP problem, anyways).
Switch from AGPGART to NvAGP. Use the Nvidia internal AGP, as that has supported NF/NF2 for a while now.
If all else fails, rmmod agpgart, delete /lib/modules/kernel.version/kernel/drivers/agpgart.o.gz or whichever, and then reinstall the Nvidia driver. It should detect your AGPGART-lessnes and use NvAGP.
For someone on dialup, it's a lot easier fix than downloading a new kernel.