I'll give a try.
Star Fox: The movie:
Act 1: Introduction:
Being broadcast across the galaxy, viewed by a tiny Fox at home in Corneria, a tiny Slippy on the family compound with cousin Grippy, a tiny Falco in the slums of Zoness hanging out with Kat and Leon, a tiny Wolf, and a tiny Andrew (with a baby Dash in the background) watching from Bolse Defense Outpost: Team Star Fox (James McCloud, Peppy Hare, and Pigma Dengar) are fighting the newly traitorous scientist Andross and his drone minions and his completely "roboformed" planet of Venom as it is attacking the planet of Corneria.
Big head mode andross happens. Every member of the Cornerian Defense Force (Including young Sergeant Pepper) gets removed from the conflict by drones or Andross. James and Peppy seem to have Andross dead to rights.... When Pigma goes traitor, blasts James into a wormhole Andross created and on James' descent, his and Peppy's quick thinking is able to make sure Andross goes with James. Andross' own hubris causes him to take the the battleplanet of Venom with him (which is the thing that ultimately plugs the wormhole and causes it to close behind them). Small kid versions of Fox and Andrew scream in horror at what happens to their relatives.
Act 2: Star Fox, The next Generation
General Pepper appeals to ace pilots Fox and Falco and ace engineer Slippy to stay with the Cornerian Defense Force rather than follow "that beloved old fool Peppy" into a new generation of a Star Fox pilot team. Falco points out the Cornerian Defense Force hasn't defended Zoness from Aparoid Incursions and he's lost faith. Slippy thinks a smaller force is the best way to test his Cornerian rejected Arwing designs. Fox explains he owes it to his father. They meet with Peppy and start a montage of training maneuvers together.
During this montage Andrew Oikonny and fugitive Pigma Dengar attack specifically of malice towards Peppy. Not expecting the three upstart pilots to come to Peppy's aid and fight the duo off, they are defeated, but not before one of them let's slip that Andross, and the planet Venom, have returned from the wormhole.
Peppy tries to assure Fox that means James could return one day as well, which Fox denies and says he's come to terms with how his father went out and he just doesn't see his father's vessel surviving the gravity of a wormhole, especially one with a battleplanet and a giant andross going with him.
Act 3: Star Wolf
Andross chastises Pigma and Dengar for attacking Peppy and Star Fox early. Peppy and Star Fox bring Andross' return to Pepper's attention. Pepper readies his pilots for defense (And we get cameos of Dash, Amelia, Lucy, Miyu, Bill, Krystal and Kat as Cornerian Defense Pilots). Pepper asks Star Fox and Falco to lead a training session as he can't think of better pilots to do so.
While this is happening, Andross' first attack, led by mercenary group Star Wolf (which Andrew and Pigma complained about the name going to Wolf, upon which Andross reminded them of their recent bungle and that Wolf is the best pilot he had ever seen. Way better than that fool James), is directed at Cornerian military installations.
Cornerian military ability for mobilization gets destroyed, but team Star Fox and the cameo'd pilots do manage to prevent the giant Sauceror (the big Independence Day Ship from the Katina Level) from destroying the Cornerian capital and the people there and force Star Wolf to retreat (after Wolf defeats General Pepper's giant mech showing how badass he is.)
Act 4: To Venom
Realizing that Corneria cannot withstand another attack, Star Fox elects to go to Venom and try to take out Andross before another attack can be ready. This just builds towards the climax at Venom and is mostly just a montage of Star Fox team fighting familiar bosses on familiar stages (Macbeth, Solar, Sector Y, and Zoness would be my picks). Crew flies well. Crew beats bosses.
Act 5: One last battle against Star Wolf, One Last Battle against Andross, One last escape.
You played the game, you know how this goes. Crew gets to Venom. Falco beats Leon (but specifically keeps him from getting killed). Peppy beats Pigma (where Peppy believes he killed him, but wishes he could be sure), Slippy beats Andrew (who flees). Fox fights Wolf and Andross together in a battle reminiscent of James' in act one. Peppy sees this and tries to intervene before Wolf forces him to retreat (on Fox's insistent orders when Peppy tries to stay at his own risk, sealing the true captain of this crew. This is team Star Fox, not team Star Hare.) Andross pulls his wormhole trick again. Fox (and shockingly Slippy) are able to make sure Fox does exactly what Peppy was afraid of and takes Andross, him, and a pursuing Wolf into the wormhole (but this time, the battleplanet of Venom does not go with them, and the wormhole is just there as Falco and Leon are unsure what happened to their captains.
Inside the wormhole, James shows back up. Realizing even with Wolf, Andross isn't sure of his own victory, Andross proceeds to try to take out the wormhole, everything inside it... and maybe everything outside of it too. Wolf is understandably infuriated by this tactic and joins with the Foxes. The trio stop Andross but they need to leave the wormhole. James leads Wolf and Fox out. Fox begs James to come with them. James says he has to stay and the wormhole is connected to more than they know. He forces the duo to go back with his last fading words being something about 'the Aparoid threat'. (combined with Falco's drop about Zoness in act 2, this sets up the sequel)
The end.
