there aren't much differences, the differences you can spot are some pokemons change. eg. in fire red you get oodish, gloom---in leaf green you get bellsprout ,veepinbell instead there are also others like for growlithe you get vulpix instead you get slugma instead of magmar in leaf green and the pokemons of the elite four also changes in both the versions there are also many other pokemons you get in leaf green which you don't find in fire red.
Firered and leafgreen both can catch different Pokemon but there pokedex is the same, here is some examples: magmar only in leafgreen not firered, oddish in firered not leafgreen, ekans in firered not leafgreen, bellsprout in leafgreen not firered, pinsir in leafgreen not firered.
Yes :)
You can't get mew in firered or leafgreen.
In Pokemon firered you can't, but in Pokemon leafgreen you can get it then trade it to Pokemon firered.
you can't only in Pokemon firered and leafgreen you can't only in Pokemon firered and leafgreen
yes
Bellsprout has to be found wild, in leafgreen, you need to trade from Leafgreen for Pokemon.
Yes, unfortunatly!:(
Migrate it from leafgreen/Firered Migrate it from leafgreen/Firered
you can not reduce evs in leafgreen and firered
Firered and Leafgreen were released in stores in 2004.
well firered and leafgreen have SOME different Pokemon so you can get those Pokemon from leafgreen. so here is the site that list the different Pokemon. just scroll down to the chart... http://bulbapedia.bulbagarden.net/wiki/Pok%C3%A9mon_FireRed_and_LeafGreen_Versions