That's not how the DSi works - for one, code can't be executed from the SD card anyway. What you need to do is connect the DSi to the DSi store, and download the games there after you buy them.
no
you have to sign in
You can only put the memory card into the computer if you have a camera. You put the memory card into the camera then using the camera cord, plug the camera into the computer then put the photos onto the computer. Hopefully that was easy enough for you to understand.
Cartridge-based games will save to the cartridge. A memory card is necessary only if you download DSi-ware games from the shop.
Yes. But you have to have the SD card. I can't play music on my DSi because I lost my SD card. If you do have the SD card inserted, all you have to do is download music from the computer to the SD card (which you have to insert the card in the computer).
You can download games/apps for the DSi via the DSi Shop.
You can download games/apps for the DSi via the DSi Shop.
as many as your ad card can hold
Yes you can as long as you have a SD card installed in your DSi. Copy pictures from system to SD card. Install SD in PC card reader and download.
You can play ds games on the dsi and you can download games from the dsi shop channel using internet access.
You can connect to the DSi store from the DSi's main menu, that's where you purchase and download games.
You download them from the DSi shop, accessed from the DSi or DSi XL's menu bar.