Loads of great advice there, thanks. Yes, it would be image processing and editing in Photoshop rather than general graphics, and I've always done that on a PC before rather than a laptop, but this time around I'd like a laptop with the ability to process images.
If I was to get a dedicated graphics card as well, is there one you'd recommend for say another £100-ish? As you can tell, it's several years since I've chosen a laptop or PC and I'm very out of touch. I'll have a look at pcspecialist now.
Thanks again.