I've been playing this game since it came out and I still havent beaten..

Hey,
I realized just by looking at your Pokemon, that you only have one Pokemon with high stats (Moltres). Stats depend on the Pokemon but seem to not matter because of level differences. However, Pokemon at the same or lower level that have greater stats can easily defeat Pokemon with low stats at a higher level.
Anyway, I see that you have two fire/flying Pokemon and a pure ground. That means if you were ever to encounter a water type, you will lose half your team, especially when your other two Pokemon can't handle a water quickly enough. In my opinion, ditch one of your fire/flying Pokemon (I think you should ditch Charizard) and get an electric. I'm not talking about Electrode or Raichu or even Zapdos (his flying part makes him vulnerable to electric). I think more like Jolteon (great electric at the fifties) or Magneton (part steel makes it interesting, but he lacks moves).
Arbok, being a pure poison, does not have a lot of Strength against the Elite Four, or anyone else for that matter (no offense). That goes the same for Machoke (he can only do some damage when he is Machamp, but still not as strong). Grab a water type (no Kabutops or Omastar, their rock part affects them just like Zapdos's flying part).
I do suggest that you ditch your team, but if you insist, you can keep Moltres.

It is always better to have Pokemon that are all completely different.

You should have all 6 Pokemon and have them all diffrent types and all above level 50 and when you are about to battle the people you should witch your party around based on the persons type of pokemon.

If you've been playing since the game came out, you should've gotten tons of leveling for some of your Pokemon, if not w/e... First of all, I would at least try to level up all your Pokemon to 48-50 (Higher would be better =P)... But I would make those Pokemon be a type that powers of each of the elite fours type... What I mean is, choose a Pokemon that the elite fours are weak against....

Before I went to the Elite Four, I went ahead, and caught the legendary birds first... I also used a psychic Pokemon (mine was haunter, Lvl 60)... I also used my Starter =P... The last Pokemon, I don't remember, but I never used it =P...

My team was

Haunter-Level 60
Zapdos-Level 53
Articuno-Level 51
Moltres-Level 51
Charizard-Level 54
?-?

You don't have to have the exact same Pokemon I have, but it would be useful to have Pokemon, that have their type...

A Fire Pokemon would be useful against Lorelei's ice Pokemon (and if she brings out water type, just bring out a thunder type if you have one)...

For Bruno, bring a Flying type (and for his rock types, either have a water/grass type prepared, or just fight normally with a fire type or something...)

Agatha, bring a psychic Pokemon to fight her psychic pokemon... If yours is strong enough, it should wipe all of hers out, or yours will get wiped out... (Not exactly in one blow if they're equal at level probably) You could also bring a dark type... But they don't have those currently running around wild in the game at your point.

Since Lance has dragon type, one ground, and one water... Have an Ice type prepared... An Ice type could take out the dragon and aerodactyle easily... For the Gyrados, just fight normally, or have a thunder type strike you down...

Also make sure that you have healing items, and revives ready to use... Er I forgot what Pokemon gary had, but I know that I beat him with the types of Pokemon I had... (Speaking elementally, even though it's not a word, you should get what I mean lol)

This is just the way I beat the Elite Four, so you don't have to if you don't want to =P

You don't need Moltres and arbok, you need a water/ice type, electrick or grass.
If you don't head a cheat device use this move sets

Charizard-flamethrower,brick break,Fly and slash

Machoke-brick break,revenge,vital throw and other moves, don't use move sets that has recoil damage.

I prefer rhydon instead of marowak with this-earhtquake,thunderbolt,rock slide and ice beam.

Your electric type, use zappy-thunderbolt,drillpeck,thunder and agility

Water type, lapras-Surf.ice beam,body slame and hydro pump/psychic

Use a grass or psychic type for your last pokemon:
Grass-victreebell-vine whip,sludge bomb,razor leaf, stun spore/poison powder
Psychic-kadabra-psychic,shadowball,mirror coat calm mind.

Elite 4 in this game is the hardest to beat in my opinion. Level your Pokemon to 70 or 75 so you won't strugle. I'm telling you they are though to beat.

Hey Oblivian Groudon I wanted to ask you were you got Articuno? Ive been searching but never found it.Laterz!