My DS4 wants a DS for his birthday and I have noticed there is a DS and a DS Lite.
Can anyone tell me the difference?

size. weight.

DS Lite is the newest version and it is brighter screen, lighter weight and smaller in size

Thanks for all the info!!

I'd go with the DS lite, for the reasons that you can barely find replacement stylus, no carry cases and no car chargers for them. AKA no accessories are for the regular DS, unless you find them second hand or on a off chance at a local game store.