CS2 to CS6 is huge, but most changes were gradual. I have two computers with the Adobe CS suite. One is running CS3, and the other is my nice machine with CS6. The CS6 one is a Core i7 Extreme, but the older one is more in line with what your running.
It has an AMD Athlon Tri-Core CPU, 4 GB RAM, and Vista 32 Bit. Even with Vista on there, I can still run CS3 pretty smoothly. I use it daily to maintain websites, so I use Dreamweaver and Photoshop a lot.
I believe that tabbed browsing debuted in CS4, but I'm not positive.
For the basics, I'd think that you'd be fine. A Pentium Dual Core is a mainstream CPU, but definitely usable. My 5 Year Old Vista machine can keep up, so I think that with a more modern CPU, and Windows 8, you'll run the Adobe stuff just fine for everyday usage.