Hi Andres - I think you need to just make sure your plug-ins are up to date.
As a reference for you, I'm including all the plug-ins I use that work with Photoshop CS6 64-bit. FYI, my OS is Windows 7, 64-bit.
With a little work and research, I'm sure you'll put it all back together and coming from CS2, I'm sure you'll enjoy all the improvements in CS6.
All the best,
Phil
Nik: Color Efex Pro 4.0, Silver Efex Pro 2.0, HDR Efex Pro 2.0, Viveza 2.0, Sharpener Pro 3.0, Define 2.0, Analog Efex Pro. Topaz Labs: Adjust 5.0, Denoise 5.0, Detail 3.1, Restyle, Lens Effects 2.0, InFocus, Simplify 3.0, Clarity, B&W Effects 2.1, Star Effects 1.1. Alien Skin: Snap Art 4.0, Bokeh 2.0. Imagenomic: Noiseware 5.0. Photomatix Pro 5.0. Totally Rad: Dirty Pictures 1.5. Flypaper Textures and Frames. onOne Perfect Photo Suite Premium 8.1. Mediachance: ReDynaMix, Dynamic Auto-Painter 2.5. Red Giant Software: Magic Bullet PhotoLooks 2.0, Knoll Light Factory 3.2. Redfield Plugins: Fractalius 1.85. Flaming Pear: Twist & Swerve. Helicon Focus Pro 5.2. JixiPix Premium Pack 2.0.