All DS systems have inbuilt wi-fi so if a game has a mutiplayer option, you can connect via your wireless router.
yes
Yes -- the DS has a built-in wireless adapter to allow for internet play in certain supported games such as Mario Kart DS.
No you cannot play D.S. Games on the internet
You can't play demos of Wii games, but you can play demos of DS games if you have a DS. They can be downloaded from the Nintendo channel.
No. Only Nintendo DS GAMES can do that!
An R4 is basically a mod chip for the Nintendo DS console. You can download games from the internet and put them on your R4 card and play the games on your Nintendo DS.
Only certain games like Animal Crossing allow your DS to connect with wifi to a computer that has internet access and play in other gamer's towns online, and let other gamers play in your town. DS does not have internet surfing ability.
no you can't play dsi games in ds but you can play ds games in dsi.
Nope. Sadly, you cannot because some of the games require a camera, the internet, etc. The DSi can play all Nintendo DS and DSL games, however.
You can play ds games on the dsi and you can download games from the dsi shop channel using internet access.
you can play game boy games a normal DS but not on a DS light or a DS I.
You need to buy them off the internet on the iPod Touch.