DraStic

but there already are widescreen hacks. for mario kart ds :P

http://forums.pcsx2.net/Thread-Unofficial-Desmume-X432R-with-option-to-increase-internal-resolution?page=24

i can confirm said hack ar codes work well with DraStic, too. if only resizing screens non-uniformly was a little easier to edit ...

so..... can you then tell me how is it gonna work on a 2 screen console? i mean do wide screen to get rid of evil black bars?
You could output the second screen to another display, or make the aspect ratio of both screens wider so that there's no black bars.
If you mean how to code a widescreen ...

Like the one in Dolphin.
snip

A modified version of desmume does it in conjunction with the Hi-Res 3d but I have no idea if its possible to add it to Drastic ds, we'll have to see what Exophase says
Can you give me a link to that version?

A widescreen hack makes sense for a console emulator ...

Like the one in Dolphin.