ret paladins are good against noobs, especially hunters that backpeddal. you might have a problem against smart hunters, though. it's all about chasing your target with that 15% movespeed and hoping for crits. with the right gear they can have high armor and health, making them tanks with giant potential to lay down a huge crit.
enhance shamans are another good 1v1 class, with a high health build they can have consistant melee damage and the ability to frost shock for kiting or catching up. probably the best hunter killer...ghost wolf up to it, frost shock, and start whacking.
rogues are good for 1v1 too but in order to beat hunters you have to LoS the hunter if it is smart. against ret palis it is all about how smart the ret pali is and how well you handle your cooldowns.
disc priests can also be good at 1v1 but it takes time and mana management. not really good at 1v1 in wsg because by the time you killed a smart twink, there has probably already been a cap. better off supporting their team. still, in arena, they are good for 1v1 if you can kite as one well and use dispel properly.
warlocks are good but very vulnerable. against a smart rogue a twink warlock has almost no chance. have to LoS hunters well and use dots, fear, and drain life depending on the situation. all depends on how well you can kite or dps while dotting down your opponent.
i've also seen good fire mages but against a smart healer they have almost no chance. plus hunters can mow them down. better for 2v2.
hunters are overpopulated and you should not roll one.
my 2c about dueling at 29