I do this every once in a while, but I always forget. We're talking Game Verse Red, not Manga Red or Smash Bros Red, etc.

>R/B
>2 years later G/S/C
>[G/S] [R/S] [D/P]
>Emerald / Platinum
>2 years later B/W
>2 years later B/W 2

Yellow doesn't count because it's anime based, including many reference's to it.

Red/Blue came first.

Gold and Silver [the sequel] takes part two years later.

At the beginning of Diamond and Pearl the protagonist is watching the news coverage of the Red Gyarados from Gold and Silver.

Emerald has Steven step down from champion, and in Platinum he appears to be in Sinnoh.

Black and White doesn't specify to take place much after; however, in one city you can find a Rocket Grunt who apparently now has a family with a child. It can be implied that he had that family after the events of Gold/Silver.

Black and White 2, is given to be 2 years later.

How old is Red?