Updating my old Comp.

Hello,
I have an old computer, a VPR Matrix 180R, and i want to rip its guts out
and put new hardware in. The only problem is i have literally no idea where
to begin. I want to get a new motherboard but i dont know what is compatable
with this system. My current motherboard specs are; Manufacturer:Intel Corp.
Model845EBT
Version:AAA92334-304
NorthBridge: Intel i845E Rivision E0
CPU: Intel Pentium 4 CPU 1.80 GHz
CPU Socket: 478mPGA
5 pci 1 agp slot

I want to buy a new motherboard and then a new processor, as well as ram and
if i have to a hard drive and a PCI-E graphics card. I know this will be
expensive, but im not asking about the cost, just what i need to buy that
will all work together. thanks