PC3200 will work because DDR is backwards compatible, although it will only run at 333 instead of 400 (unless you overclock). If you plan on doing any overclocking, then you'll want to go with the PC3200.
You can run the memory at 400Mhz and the CPU at 333Mhz with this board. If you do it right, you might actually be able to run the Barton at 400Mhz. Just need some good cooling.