What's the best route to take buying devices for post processing and general computing?

Christmas is coming soon, hooray!

And with it comes the problem of replacing my aging old Dell Vostro. It's stood up to the test of time somewhat from the abuse it's suffered during the past 2-3 years, but is really starting to struggle with running Lightroom and Photoshop, and no doubt compilers when I have to start programming again.

So what devices would "The Lens" recommend? I have somewhere slightly above £1000 to throw in to a device or two that handle my day to day browsing and word processing, can happily run a compiler and most importantly, will fly through photo work in Photoshop, Lightroom and MS ICE. The vostro was 14" and I love the size, but I need something with a higher resolution screen (1080p or higher), an SSD (based on recommendations from just about everyone), a battery life that will suit me traveling with work this year and going back in to study next year, and decent future proofing (Haswell, decent build quality, maybe touch screen?).

Basically, from a photographers point of view, how should I purchase my next device, focusing on the following:

  • Laptop? Or desktop (and chromebook/android tab for lecture work and internet consumption)
  • i5 or i7?
  • Best middle ground for SSD?
  • Screen will be bought at some point for home use, what to be looking for?
  • Is going MBP worth the extra investment
  • Is dedicated graphics important? Should I only buy Iris Intel chips?
  • what laptops have a good colour range for the screen?