When picking your appearance you can use 
(PC) or the 
(Xbox) to spin the head. This is especially useful when choosing a hairstyle as some are longer than they look from the front. When it comes to gender, females of some races have slight differences in their skill bonuses, but as a rule you should choose a gender based on personal taste.
Orc
More commonly called "Orc," Orismer are some of the greatest Armorers around, and their skill with blunt weapons is unmatched. Orcs, along with Redguards, are the combat specialists.
Breton
Bretons are one of the best choices for mages as they have significant magic resistance. Bretons, along with High Elves, are the champions of magic, but you could turn one into a fighter with a little extra effort.
Imperial
Imperials are the most respected and well liked of all the races. They are good at persuasion and trading and fairly well balanced in all of the skills. Imperials are the most balanced race, as other than a slight combat leaning they're pretty much mediocre at everything.
Redguard
Redgaurds are some of the greatest warriors ever. Redguards, along with Orcs, are the combat specialists.
Nord
Nords are even stronger than Orcs and have a strong resistance to frost magic.
High Elf
High elves are the most powerful mages in the game, at a cost of physical weakness to magic. High Elves, along with Bretons, are the champions of magic, but you could turn one into a fighter with a little extra effort.
Dark Elf
Dark Elves are the most balanced race in the game and can make decent Warriors, Assassins and Mages, since they have bonuses to Destruction, Marksman and Blade.
Wood Elf
Wood Elves are masters of stealth and ranged combat. Living most of their lives as Hunters and Woodsmen, their knowledge of the forest and the bow are unmatched. Wood Elves, along with Khajiits, are natural thieves.
Argonian
This race is seemingly the least liked but can breathe underwater and are immune to poison. Argonians can swim any distance underwater (useful for treasure hunting).
Khajiit
This race can see in the dark and they are experts in sneaking. Khajiits, along with Wood Elves, are natural thieves.