For a finite subgroup Γ ⊂ SL(2, C) and for n ≥ 1, we use variation of GIT quotient for Nakajima quiver varieties to study the birational geometry of the Hilbert scheme of n points on the minimal resolution S of the Kleinian singularity C 2 /Γ. It is well known that X := Hilb [n] (S) is a projective, crepant resolution of the symplectic singularity C 2n /Γn, where Γn = Γ ≀ Sn is the wreath product. We prove that every projective, crepant resolution of C 2n /Γn can be realised as the fine moduli space of θ-stable Π-modules for a fixed dimension vector, where Π is the framed preprojective algebra of Γ and θ is a choice of generic stability condition. Our approach uses the linearisation map from GIT to relate wall crossing in the space of θ-stability conditions to birational transformations of X over C 2n /Γn. As a corollary, we describe completely the ample and movable cones of X over C 2n /Γn, and show that the Mori chamber decomposition of the movable cone is determined by an extended Catalan hyperplane arrangement of the ADE root system associated to Γ by the McKay correspondence.In the appendix, we show that morphisms of quiver varieties induced by variation of GIT quotient are semismall, generalising a result of Nakajima in the case where the quiver variety is smooth.