Yes you can. You can also connect DSi to DS and DS Lite to DSi.
Yes you can. You can also connect DS lite to DS and DS Lite to DSi.
For the most part, yes you can. If you want to connect with pictochat or DS games (including DS Download), you can connect between a Nintendo DS and DSi. However, for DSi specific games, such as DSi games and certain applications, the Nintendo DS will not be able to connect. But, note that certain DSiWare games that can DS download play still can be connected to the Nintendo DS.
A DSi uses DS games.
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)
there is a problem with it
Yes, the Nintendo DS lite can play DSi games
The Nintendo DSi is just an upgraded version of the Nintendo DS and DS Lite. The Nintendo DSi plays the exact same games as the Nintendo DS and DS Lite and only plays DS and DS Lite games. Currently, there aren't going to be any DSi games, only more DS games.
Yes, you can play DS lite games on the DSi as well as the DSi XL
no, you can't download game to a Nintendo DS lite, it only works with a Nintendo DSi or a DSi XL
Yes Nintendo ds games work on DS, DS Lite and DSI. The DSI does not support gameboy advance games but the DS does.
Probably can. Try it out.