What amp? Series or parallel loop?
I would do flanger then delay. Though it depends on the pedals and what options they offer of course.
I don't know the exact input config of the Zuul, and I think there are multiple versions, but honestly if you are running the amp listed under your avatar and your pickups and shit aren't super noisey, I would just get rid of it.
Solid State amps usually don't need gates, one of their benefits. I have a VH-140C, and it's much quieter than my tube amps.
If you do need the gate for whatever reason, it would help if you specify where the noise is coming from. Unless you have something else that is mega noisey, I would just put it after the guitar or the OD and nowhere else.
If you do want the zuul in the loop, i would do it before the flanger and the delay, though once again it depends on what models and settings and etc. etc. etc. and whether you are using the flanger for heavily effected signals or just kicking it on for a little added juice on solos or whatnot.