Yessir, although one may not send pictures/take pictures, to the older Gen ds because it just doesn't harbor the camera progrum. For example, me and my buddy Jahn traded shitloads of pokémonz to each other and i have the dsi. i later took an embarassing picture of him sleeping on another man, but could not send it to my friend Mo because he also has the regular ds.
Yes, it is fully compatable.
Yes, all models of the DS including the DSi models, can communicate with each other using their internal wi-fi.
No you do not, as DS games do not rely on or interact with DSi software.
Yes, you connect to the DSi store wirelessly.
no you can't play dsi games in ds but you can play ds games in dsi.
There are five DS's: -DS -DS lite -DSi -DSi XL -3DS
FYI, if it is out for DS, it is out for DSI.
No. The DSi and DSi XL does.
Yes Nintendo ds games work on DS, DS Lite and DSI. The DSI does not support gameboy advance games but the DS does.
There is no such thing as "DSi Lite" but let me tell you this: at the moment of writing, ALL DS games fit in ALL DS's (DS, DS Lite, DSi, DSi XL)
They are for ALL DS SYSTEMS, DS, DS lite, DSi, and DSi XL.
No -- there is no sanctioned accessory that will wirelessly display the DS screen on a TV.