I want to make a spell that makes spellcastingin a given radius impossible for a given amount of time, can anyone think of a way to do it? I have the visual effect (a swarm of black bees) accomplished (it looks great) but I can't figure out how to make spellcasting within a given radius impossible.

You could try reducing magicka to zero.

My system doesn't operate on magicka, actors have a given number of casts per day per spell.
EDIT: Maybe there is a way to ForceUnequip spells? Some way to keep them from being able to equip spells for a given amount of time?

If actors have a given number of casts per day, then you must have some way of keeping track of how many casts they have remaining. In which case, you could retrieve that value, store it, set the value to zero, and when the effect is over set it back to what it was before.

My system doesn't work that way unfortunately. Basically the system is a global that maintains how many casts remaining, and if that hits zero and they try to cast, it removes the spell from them permanently (until, if it is a character, they rest) so if I did that they would just continue casting once per spell, and then would permanently lose each spell in succession.

Can't you grab that global?

Oh wait, derp, I forgot that NPC spells don't work the same way as characters where they have limited casts per day. They are basically spell barrage machines until they die. So...I guess I could make a formlist of all the NPC spells in the game, and then iterate through the formlist unequipping all of them. It just keeps looping through that while loop until 30 seconds is up, and then it breaks and they can equip spells successfully again.

_{I have a similar spell, what I did was registered for an animation event looking for spell cast right and spell cast left. Once those are triggered you can try the interrupt spell function or remove spell function.}

That's a good idea. I also think I may be able to leave it as just a swarm of bees, as just they themselves make it pretty much impossible to hit anything with a spell.

Not sure if its relevant to what you need but you could try InterruptCast()
http://www.creationkit.com/InterruptCast_-_ObjectReference

make a spell with a script effect for interrupt cast, and then use a cloak effect to spam it onto anyone in the affected area

Not sure how cloaks work exactly, but I'll look into it. Sounds like the right idea.

If you want to force the caster to use weapons I think you need to remove the spells. Wouldn't interrupt just cause them to constanty stutter trying to cast spells effectively incapacitating them?

I think what I'll do is unequip spells and disallow requipping as the effect of my cloak.