>>21509206>Great Games you shouldn't miss out on:HeartGold/SoulSilver (DS, Remake of Gen 2 that eases old players into the newer stuff well)
Platinum (DS, the Gen 4 counterpart to HeartGold, very good)
Black2/White2 (DS, Sequels to B/W, so you may want to consider picking that up first. Has a very large PokéDex giving you a great variety of Pokémon from all Regions. B2/W2 also lets you battle every single Champion and Gym Leader from the first 5 Gens, including Red, something fans had asked for for a long time.)
>Most recent game to be up-to-date:AlphaSapphire/OmegaRuby (3DS, can also be played on the cheaper 2DS. Remakes of Gen 3, that will also easy older fans into the mechanics and new Pokémon of Gen 4-6. Online features are greatly improved and simple to use)