Bearded Dragon hands down. SAvy monitors get real big, and eat a lot. I really suggest you go out and do your own research and don't listen to one thing that comes from a pet store employee.
A leopard gecko, or blue tongue skink might also be good choices for a first.

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LIZARDS
0.0.1 Monkey-Tail Skink- "Bubba"
1.1 Irian Jaya Blue Tongue Skinks- "Sammy & Sausage Girl"
1.0 Indonesion BTS- "Don"
0.0.1 Tanimbar Island BTS- "Sebastian
1.0 Kei Island BTS- "Huckleberry Blue"
0.0.1 Ornate Uromastyx- "Spike"
0.1 Albino Leopard Gecko- "Sasha"
SNAKES
1.0 Green Tree Python- "Pink Floyd"
0.0.1 Sonoran Gophersnake- "Toro"
0.1 Western Hognose- "Piggy"
CHELONIANS
0.0.1 Egyptian Tortoise- "Tank"