The best pet lizard?????

Not an iguana, most people use them as disposable pets (once they get too large or aggressive people give them away or let them go). Bearded dragons are the best lizards if you are willing to put time into cleaning, feeding, and handling. I got one for my brother for his 11th birthday and he has been very capable of maintaining it properly. Iguanas on the other hand tend to be very aggressive and can grow in excess of 5 feet! At full size their bite can be very serious, so I recommend not getting one until you are older and more experienced. A bearded dragon would be happy in a 20 gallon tank, but a bit bigger would be ideal.