What are you playing? c'mon, tell me punk!

[Jermungandr]

I honestly would probably suggest jumping straight to the most recent game. The Monster Hunter games don't have any sort of continuity, and since a lot of monsters are recycled across each new iteration, you wouldn't be missing much skipping ahead.

Plus the latest game is supposed to be the most newbie-friendly, with significantly better training elements for newcomers to the series, so it honestly sounds like the easiest one to jump into with no prior knowledge anyways.

Also since everyone seems to be trading up to the latest edition, it's going to be easier to find people to play with you if you own 4, I assume.