Will 800Mhz DDR2 64 x 8 work on a M2N32-SLI Deluxe motherboard?

Answer 1

Yes, you should be fine using that memory for the M2N32-SLI motherboard. Asus website states that it will accept the following memory configurations:
Dual-channel DDR2 800/667/533

That does not necessarily mean that you have to run the motherboard in Dual-channel mode only that is supports it with those types of memory modules.

I would recommend getting a good, name brand memory module for use with that motherboard such as Corsair (Me personal choice) Crucial, Geil or OCZ.

If you want more info on this motherboard read through your manual that came with it or look on ASUS website. Good Mobo