The scale of the races slightly affects melee damage, speed, and jump height. I've also heard that your races 'size' (muscle mass) affects stagger, knockdowns, and getting toss around.
So, with that formula, Bosmer deal the least base melee damage, and move slower, while Altmer move faster and do more melee damage. However, Altmer have the lowest 'size' so they get smacked around easily in combat. Orcs and Nords are the best melee fighters because they have the highest 'size', and the 3rd and 2nd highest scales, respectively.