Yes, the Pentium G2020 is a good budget CPU for the price.
The pentium G2020 should perform faster than the Core 2 Duo E8400 at stock speeds.
Pair it with a dedicated graphics card like the GTX 650 Ti or HD 7770 and should be good enough for gaming.
All of the graphics cards you mentioned were over £100 would`nt it be cheaper just to get a better cpu? Or am i talking balony(light gaming being minecraft).
You said light gaming.
Graphics card such as the HD 6670 or HD 7750 is enough for casual games and light gaming.
Most games run well on dual core CPU.
But next generation console will use more CPU cores and more threads.
That is why most people recommend Core i5 and Core i7 as they are quad core processors and are much future proof compared to Pentium G2020.
If you're on budget and want to upgrade later to i5 or i7, the Pentium should do well for now.