Best team that I've found for Fire Red- (Yeah, alot of OU Pokemon coming up but guess what? They work.)
Ditch the starter, swap for Scizor. (requires Trade, Metal Coat)
Flying pokemon- Aerodactyl
Tank-Tyrannitar (End game destroyer, love this guy)
Mixed sweeper- Dragonite
Special Specialist- Alakazam
Extra pokemon (I never need 6 for in game, so this one changes alot)
Nidoking/Electabuzz/Vaporeon/Kabutops/Arcanine or Chansey.
In all honesty, in the game against NPCs there's really no bad combination, just using what you like will get you by, even if they have bare minimum EVs and IVs, as long as they have a decent, balanced moveset. Even types don't matter if you have a move to counter the opposing type.