I really dont no atall.
no
No you can't use Game Boy Games on the DSi
No, you can't play GBA games on DSi, only DS and DS Lite.
Yes, Ds games work with the Dsi as well, but not Game-Boy games
yes you can
For the GBC (Game Boy Color) I don't know of any hacks... For any GBA (Game Boy Advanced) games, you use a GameShark... For any DS (Dual Screen) game, you use the Action Replay... But the Action Replay doesn't work for the DSi, the one for DSi is rumored to come in September
Yes. they both use the same types of games! yes
No. It is bad because no Guitar Hero for DS and You can't migrate Pokemon.
The DSi is not region-locked, it can play a Japanese game regardless of where the DSi came from.
yes
The DSi is totally worth buying! On the DSi there is a camera- you can alter photos you take, you can download games and use the sound recorder plus everything the DS does apart from playing the game boy advanced games.
No, you can't. Super Game Boy is only compatible with Game Boy and Game Boy Color games.
No. The charger for the original DS is only compatible with the DS and Game Boy Advance. The charger that the DSi XL uses is the same as the one used by the DSi and 3DS.