I have half of my team thought of already, but what should the other half have? I'm looking for a good wall(both special def and defense). Here's my proposed training for the ones I have right now:
EVs will be 200 Def, 252 Sp. Def, and 52 HP/Sp. Atk [Bold or Calm]
EVs are 252 Atk, 252 Speed, the rest on Sp. Atk [Naughty]
EVs will be 252 Sp. Atk, 252 Speed [Modest]
Help is appreciated

If you want a good pokemon to wall on both sides of the spectrum, might I recommend Celebi with a 100 base stat in both defenses, or Cresselia who has base 120 defense and base 130 special defense, or Latias which has 90 base defense and 110 base special defense which can be boosted by calm mind and it has access to reflect. Those are some pokemon I could recommend as a wall.

Now as for the rest of your team pick pokemon that can cover the weaknesses of your other pokemon. A Jolteon might be good because people like to dish out T-Waves and the like on fast sweeping pokemon, and with his Volt Absorb ability is a good way to throw that off. Just be sure you can cover the big weaknesses of your team for what ever pokemon you decide to use.

add a weavile for amazing attack and the speed to accomplish the deed

(Ev's in ATK; Spd.)
Night Slash
Aerial Ace
Ice Punch
and something else

or you could add a Torterra, they have exzcllent defense is played right, even against an ice type.

I would suggest almost any ground, rock, or steel-type. Aggron (lv 66) is my wall on Emerald in the Battle Fronteir, and can last in a battle against lv 80s. Either that or Rhyperior, which is imune to Electric types, making up for your Blastoise's weakness there. Suggested moveset for Aggron is Aerial Ace, Surf, Rock Slide, Iron Tail.

i'm agreeing with Khoufu.
Steel and rock are excellent choices, just because they are sturdy ususally and easily learn powerful and useful moves quickly.

khoufu, Aggron has horrible special attack. I recommend you get rid of Surf in exchange for something physical.

Anyway, I'd like to know a bit more about the team. Could you tell us the movesets?

But if you want a mixed wall, then use Skarmory/Blissey, or try Tyranitar.

Yup, and two 4x weaknesses to very commonly used types and a water weakness is good for a wall. Not to mention Arrgon's 50 base s.def

/sarcasm

Ok, sorry, I guess Rhyperior or Steelix is better. And I can get rid of Surf on DP for Waterfall but I can't replace it on Emerald cus it's my surfing/strength pokemon. Rhyperior is immune to electric attacks, so I guess that's a good wall.

The definition of a wall is- a pokemon that can take loads of damage without breaking a sweat. Just because it has an electric immunity doesn't make it a great wall. Cresselia is a much better wall than Rhyperior can ever hope to be because of an access to a recovery move, access to Reflect and Calm Mind, the ability to cripple other pokemon with Thunder Wave. Also wall pokemon are also there to stall out opponents, and spread out some status ailments too, say Moltres with Roost Substitute and Toxic, Moltres is a difficult pokemon to take down with the right ev spread, so all Tres has to do is Toxic the other pokemon survive the hit Roost off damage and do whatever. In essence immunities are nice on a pokemon that is supposed to be a wall, but they are not everything.

In that case Arceus would be a great wall in most cases, because of it's huge HP and access to almost any move, and it comes with Recover. That or Mew, though its defense isn't the absolute best, but has access to the most moves.

First off if by most cases you mean the Uber metagame which is the only place you will ever see an Arceus in battle then no. Absolutely not. Arceus is outclassed in the Uber metagame as a wall by what I call the big 3 walls and they are Deoxys-D, Lugia, and Giratina-Another Forme.

Secondly back to the topic at hand. Magnezone can be an asset to your team. It's typing give it immunity to being poisoned, resistant to the ever popular bolt beam, it isn't afraid to take a Dragon Claw or Outrage because of a resistance to that, give it Magnet Rise and its biggest weakness which is ground is null and void. It's variety of movesets is good, and it can surprise anyone because of the many Hidden Power types that it uses oh so well.

EDIT:Or if you don't want to use Magnezone for fear of your team being to special based I suggest what I call its physical counter part which is Metagross. Pretty much the same resistances/immunities, but Metagross fears one thing which Magnezone doesn't and that is being burned. Metagross can be tank (which is a pokemon that can take damage and dish it right back). Those are just two suggestions that I thought of to help you out.

Edit *burn removed*: I give up, from now on I'll just ignore your posts.

Back on topic, I'd agree with Shinshu Taji's Metagross idea. It can really take a hit, and gets decent type coverage complimented by it's great offensive stats. Picking a tank can pretty much come down to personal preference, and what can fill in for the waeknesses on your team. It's always heartwarming to switch in on an attack that is nullified or weakened by the pokemon's ability/type and then be able to stall.

To be fair, Theo, at least theres been no mention thus far of "Pikachu! Aim for the horn!"

That might have been a bit to far theo, to be fair.

But its true. Khoufu, you need to either stop posting advice or think a bit before posting because a lot of your "advice" is pretty much what Theolithical just said.

Ok I'll stop. Sorry for giving noobish 'advice'. I guess now I'll stick to the General Discussion forums until I learn more about pokemon.

It's sad that I know what this is referring to...



On-Topic:

Actually I tend to use my Mismagius as a mixed wall of sorts.

Mismagius
Calm @ Leftovers
252HP 204DEF 52S.DEF
-Will o Wisp
-Protect
-Icy wind
-T-bolt/Shadowball/Psychic

Assuming you breed a 31IV in HP and DEF it should be able to survive up to a max adamant, life orbed, metegross's meteor mash. Of course being faster a burn will drop it to a 3hko. Protect to recover HP and let burn reduce. Icy wind gives light damage and one hit will make anything +120 base slower to allow a follow-up hit or to slow an threat switching in. Last slot is preference: shadow ball is STAB, T-bolt gives great coverage, and Psychic hits infernape and heracross hard as they can't be Wow'd. I guess Destiny bond can be used there too as it can do well w/ icy wind, just beware of taunters.

because i can obviously get a legit one xP I'll go with cress next then. see how that works out.

Claydol w/ leftovers
Bold
252 HP 128 DF 128 SD
Ice beam
Earth power
Protect
cosmic power

Simply alternate between protect and cosmic power till both Claydols stats are maxed then attack
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