>>52033160I'll give you a quick rundown on grinding in each pre-gen 6 game:
>Gen 1It's the first game and grinding in it is pretty lousy. You only have wild pokemon to train off of. The good thing is that it's the easiest gen, so you can raise 6 pokemon and not suffer too hard. Watch out for Alakazam though.
>Gen 2A bit worse than Gen 1. Grinding still isn't good, but opponents are more threatening. Whitney will kill you if you aren't managing Exp right. The E4 and Red can be tough. But you do have Badge Boosts so it's not that bad.
>Gen 3Legitimately awful. I hate grinding in Emerald. Emerald's Exp grinding also sucks but it's way harder than Gen 1 and 2. The only way to grind is by chasing around Gabby and Ty for rematches, but that eventually falls off because they cap in the 30s. Wild mons don't do much for you either. Catch the Rayquaza/10
FRLG is the first game where grinding is easy because it adds the VS Seeker. It is very easy to have a team of six in FRLG.
>Gen 4DPPT also has the VS Seeker so having a team of six is easy. It's also easier to get a Lucky Egg in DPPT than FRLG. HGSS though lacks the VS Seeker. I would say that despite being the slowest, DPPT is actually the fastest game for grinding.
>Gen 5Gen 5 drops the Exp Share unfortunately, but it hands you a Lucky Egg for free and you can rematch Breeders. A bit worse than DPPT, but it's something.