The AK2 works very well the the EZ 3in1 when used with AKAiO. It will auto-load GBA backups located on the Slot-1 into the Slot-2, on the next load, it will backup the save onto the Slot-1.
If your wireless card support the Access Point mode you should be able to connect with it, but keep in mind that you'll need to get an Internet access from another mean (wired connection) to the laptop which act as a bridge between the ISP and the console.
From past experiences, DealExtreme is a choice you can consider. If you're not in a hurry, you can save over the slow shipping. Plus they have a ton of those small pieces of equipment, like cheap HDMI cables, etc.
I got tired of using my Nintendo DS as a media player, it is just not its purpose.
I got a Creative ZEN, on which I put my DiVX files on it and play when I need them.
The SSID broadcast must be activated on the access point, since the homebrew use a wifi driver that currently doesn't support connections to a hidden SSID.
I used my R4 in the past, and I currently use my AceKard 2.1 + EZ 3in1 with DSLinux. As said above, my virtual keyboard is also a bit imprecise, but it did that on my R4 too. So I guess it's DSLinux itself that is not calibrated properly.
Clubhouse Games, if you want to play some games like Texas Hold'em, Chess, etc. Only require one cartridge for up to 8 players, depending of the games. (Obviously, only two users can play chess at a time)