Yeah, HeartGold & SoulSilver are enhanced remakes of the original Gold/Silver. The graphics & all that are updated to be better than D/P. There aren't any new Pokemon in the games but later on you can get some of the non Kanto/Johto legendaries, but they don't really interfere with the story. If I were you I'd just pick up a copy & play through without any other info. Have fun, rediscover Johto, & the let the good times roll.
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