All things considered, lawful good.
I know you're probably gonna say you'd be Mario and all, but being lawful generally means doing things more for a cause or to accomplish something and less for the heck of it... It's a common misconception that lawfulness in alignment literally means how much one obeys the law or kisses up to authority figures when it's more about how much a purpose directs actions. You'd be more LG because you do what you do for the forces of news.
Mario being NG (sometimes called "true good") makes more sense than LG because while he does fight for the forces of good and justice and to save those in danger, he doesn't really think about it that much, and just does it. For example, if Mario were LG, in Paper Mario 2's last battle sequence, he'd have a bigger problem with attacking Peach because part of his code would undoubtedly be to serve and protect her. Which isn't to say he wouldn't ultimately decide to fight her. Goombella brings up that it might not seem right, but Mario himself just sees that Peach is evil now and gets to the stomping without hesitation.
Nerd alert: it's me! Well, you asked, so there you go
