First of all, your best bet is to start with a leader class, and multiclass into controller, since going the other way around only really gets you healing 1/day, while most of the controller's schticks come through their powers.
As for race, half-elf is a good choice, since his dilletante power gives you access to another controller power (and you can make it at-will with an extra feat at paragon).
Bard is probably a good way to go, since as an arcane caster he's already a bit on the controller side (you'd likely want to go with the Cha + Int build in that case). Bard allows you to multiclass multiple times (which you can use to grab powers from multiple controllers, since many give you an at-will power as an encounter as part of their initial multiclass feat). Also, half-elves have access to a feat that let's you treat all powers you gain via multiclass to be charisma based, so you only need to meet the minimum requirement for going into other classes.
A paragon multiclass with the bonus from the bardic dilletante feat gives you access to ALL class powers for your encounter/utility/daily options. Depending on what level you are starting with, there are some paragon paths/epic destinies that let you grab powers from outside bard.
So, long story short, a half-elf bard is probably your best bet. On top of everything else, wielding a wand gives you access to additional powers as well.