In regard to the two memory card slots on the 800, does it make a difference which slot is used for a higher capacity card? For example, I have a 4GB and a 2GB that I want to use. Does it matter which slot I place the 4GB card in?

The main difference between the slots is that the internal (under the battery cover) is meant not to be removed during operations as you can set swap on it.

The external card is more for being removed so the main choice is will you ever want to remove the card?

If you have a limited set of data you want to keep on the N800 all the time then put the smaller card inside. Also, when you use swap the card is not accessible from the USB cable so the smaller card inside is probably better then you can keep music and movies and such on the external card and change that data around if you like.

Really? I have 128MB swap on the internal card and when I plugged my N800 in to upgrade the firmware, Ubuntu showed both cards on the desktop. Is this perchance a Windows thing?

nope, I have a 128mb sd in my external slot, and 4gb sd in the internal slot and they both show up just fine under vista, I can even see the swap file.