My favourite types are bug, grass and water types. Rock and fighting types are pretty nice too. My favourite pokemon is Heracross, and even in gen 1, bug types themselves weren't that bad (I consider Pinsir especially underrated). Also, in generation 2 there was forretress and scizor. Bug/Steel pokemon have only
one weakness. How badass is that?
My least favourite is Ice. It's just... give
any pokemon an ice typing and it makes it
weaker. You might as well get a water type with Ice moves. Give any pokemon an ice type and it makes it worse. Ice
attacks are VERY good, beaing able to do 2x damage to four different types. They're especially useful against trainers like Lance. But as I mentioned, no point in getting an ice type pokemon when you can just teach Ice beam or Ice punch to your main special attacker on your team (of course in gen 4, you'd teach ice punch to a physical attacker).
Idocreating said:
At least in Gen I and II, Ghost Pokemon are utterly useless to me. The anime specifically has Ash aquire a Haunter in order to defeat Sabrina after her psychic moves kerbstomp him.
Ingame? Psychic types are super-effective against Ghosts. Psychic moves/Pokemon are a must have in my team, so I'll bumrush for a Butterfree asap.
Firstly, psychic is normal against ghost. However since ghastly/haunter/gengar are also poison type, they take 2x damage against psychic moves.
Ghost pokemon in gen 1 and 2 were very good special attackers. Since ghost moves were all physical until generation 4, you wouldn't teach ghost type attacks. Give a gengar moves like psychic, thunderbolt, ice punch, etc. Gengar is very versatile in that way, and can do serious damage to nearly any pokemon.
But whoever said "Use bug and ghost pokemon against Sabrina" needed a slap in the face, because it definitely was not true in the early generations. AFAIK ghost moves weren't even super effective (they did nothing?) against psychic pokemon in generation 1, and the first good bug move was in generation 2, megahorn, which could only be learned by heracross, which takes double damage from psychic types. There is some very strange advice in the anime...