If I was todownload a rom that is from the USA,would it still work in my EUR/PAL ds or do I have to do something to is as you would with Wii games?
The Nintendo DS doesn't use region coding. The country code of the ROM indicates the region in which it was released and typically indicates the language support. (i.e. USA ROMs only support English, E (European) ROMs will typically support ENglish, French, German, etc.)