There's more to it than that. Criticals earn you a chance at an increase, but you can also use Glory to boost stats directly, no rolls required. That's a winter-phase thing.
On to the combat.
Player | Result | Enemy Result | Enemy |
Rodric | Success (12<=20) | Failure (14>10) | Saxon Warrior #1 |
Cedwyn | Success (3<=20) | Failure (18>10) | Saxon Warrior #2 |
Rodrick rides down on the one on the right, and scores a solid hit, doing 11 (19-8 for armour) damage. The Saxon is still on his feet, but Rodric's spear shatters.
Cedwyn charges his target on his massive horse and also scores a hit, doing 18 (26-8 for armour) damage. The Saxon Warrior drops to the ground incapacitated, and Cedwyn's spear stayed intact.
Actions?
[Cedwyn can charge the remaining saxon, but Rodric would need to disengage and charge next round. That's usually an option in non-battle melee.]