GB advance, SP or DS lite ?

[Super_Boom]

If you don't have a 3DS (or never had a DS in the past), I'd say go with the DS Lite. Once you finish your GBA games, you'll have access to the incredible DS library.

If you do/did have a 3DS, or care more about playing original Game boy cartridges, go with the GBA SP. I'd still say GBA+DS Library > GB+GBA Library, but I won't pretend to know your preference.

Don't bother with the original GBA. I liked it at the time...but a handheld that needs replacable batteries seems so outdated nowadays.