It depends on what you prefer. Everything has a weakness. My personal favorite - Charizard - is pretty much dead when put against electric or water types. However, it is generally accepted that Mewtwo is the ultimate pokemon from the originals. However, because it is psychic, bug and ghost type moves will still super effect it. Dragonite is nearly unstoppable, unless you have ice power, or another dragon type.
I reckon it would be Blaziken (fire/fighting), Breloom (grass/fighting), Sharpedo (water/dark), Lanturn (water/electric), Aggron (rock/steel), and Camerupt (fire/ground)!
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While this does present a good example of a balanced team, you should choose Pokemon that you feel comfortable battling with. However, try to avoid having only 1 type of Pokemon in your party. My PERSONAL party has only 4 Pokemon, some of which I have traded from other games: Blaziken, Quagsire, Jolteon, and Altaria.
Probably one of the ubers here's a list:
http://pkmn.net/?action=page&id=8401
I recommend Kyogre or Deoxys
According to Silphroad.com, it looks like Mewtwo has the highest stats.
pikachu!!!!!!!!!!!!!!
All of the starter Pokemon are the best
pokemon blue
Venusaur, since its a starter. Or Victorybell.
Electrive Electrive
cinabar island
Has to be Blue, In my opinion.
mewtwo
A blue gummi is a food item in Pokemon Mystery Dungeon that increases your IQ. It works best for Water-type Pokemon.
Voltorb is the best choice cause he isn't useful
Easily Pokemoncheatscodeswalkthroughs. There are few really good Pokemon sites out there for Red and Blue (Kanto), and this is by far the best. Note that this site is constantly updated: www.pokemoncheatscodeswalkthroughs.webs.com
There is no best Pokemon. All Pokemon have type advantages. My best advise is to get a flying Pokemon, an electric, a grass, water, fire, and a rock/ground Pokemon (Geodude is good)
Pokemon Red & Blue with 23.9 Million copies sold as of 2009.