Welcome to Gaia! ::

I've got the knowledge for Pokemon Emerald, especially good Pokemon and their best moves.
Sandslash: Rock Slide, Sandstorm, Earthquake, Slash
Salamence: Dragon Claw, Fly, Fire Blast, Hydro Pump
Medicham: Hi Jump Kick, Psychic, Shadow Ball, Mind Reader/Icepunch
Gengar: Hypnosis, Dream Eater, Curse, Nightmare
Metagross: Explosion, Earthquake, Meteor Mash, Psychic
Espeon: Psychic, Bite, Baton Pass, Quick Attack
Umbreon: Bite/Faint Attack, Quick Attack, Confuse Ray, Moonlight
Gyarados: Hyper Beam, Earthquake, Bite, Hydro Pump
Swampert: Earthquake, Surf, Counter, Mirror Coat (breed from a male Corsola)
Exeggutor: Solarbeam, Psychic, Sunny Day, Egg Bomb
Xatu: Psychic, Drill Peck, Steel Wing, Teleport
Butterfree: Silver Wind, Gust, Sleep Powder, Dream Eater
Rapidash: Fire Blast, Bounce, Double Kick (breed from a male Combusken/Blaziken), Stomp
Dragonite: Dragon Claw, Fly, Hyper Beam, Thunder
Machamp: Cross Chop, Hyper Beam, Rock Slide, Counter
Huntail: Hydro Pump, Crunch, Rain Dance, Ice Beam (same with Gorebyss but with Psychic instead of Crunch)
Slaking: Focus Punch, Hyper Beam, Thunder, Counter
Pinsir: Guillotine, Rock Slide, Submission, Faint Attack
Blissey: Toxic, Aromatherapy, Softboiled, Hidden Power/Thunder
Hitmonlee: Mega Kick, Reversal, Endure, Rock Slide
If there are any other Pokemon that you need help with the attack choices and all of that stuff, contact me DoubleZ_is_cool at doublez@live.com

your gengar set fails in my opinion
why does espeon have baton pass when there is NOTHING to baton pass
gyrados shouldn't have hydro pump, since its sp. atk is low
exeggutor could have earthquake and replace egg bomb with body slam
rapidash shouldn't have bounce
dragonite should have dragon dance instead of fly
take off teleport on the xatu
butterfree should have psychic
i dont feel like fixing every pokemon set though

if anyone needs help with pokemon sets, go to www.smogon.com