I would drop Wario Land, definitely. Not that it's a bad game, but it is CLEARLY not a Mario game at all.
Yoshi's Island at least actually features Mario and got re-released as a Super Mario Advance title. I don't personally consider it a mainline Mario game, but I can see the case for it.
As far as Donkey Kong goes, from a pure mainline Mario standpoint, I would skip it. It belongs more in the Donkey Kong series along with DK Jr, DK 3 (lol), and the Mario vs. DK series. Again, the Game Boy version is a fantastic game, but if you're looking for Mario purity with this project, I vote no.
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Thank you, Eddie Guerrero.
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