To be honest - what's your budget first?!
Then just buy one with the best processor you can afford, i7, i5 minimum, ensure it has 8GB memory and a decent screen/display and that's all you'll need.
On board graphics are more than adequate for your needs - separate graphics cards are geared towards 3D rendering so most of the work will still fall on your CPU to do.
If you can afford the SSD for OS, then great, but ensure you have a decent additional storage drive (internal or external) and back it up often.
The last choice then is - PC based or MAC based