In that case, I would stick strictly to either Canon or Nikon. Nowt wrong with other brands, but there's not a good enough reason to switch for the purposes you're after.
Is it a surprise present? If not, then I'd take your Dad into a shop and get him to try out the cameras at the budget end of their ranges. IIRC that's the Nikon D3300 and the Canon EOS 1200D at the moment, although you'll probably find some bargain D3200s around as well right now. Doesn't matter which shop, you're not going to buy from there so even Currys will do.
I think I'd be looking at the 3300/3200 more than the 1200D, as I believe the screen is slightly bigger on the rear. I also happen to be a Nikon person myself though, so may be slightly biased When I tried both brands back to back, there were less irritating features about the Nikon than the equivalent Canon, but then that's a very personal thing. Either of those bodies mentioned will give great results with a decent lens, and tbh that's where the real money you have to lay down is. Depending on what the project is, a bundled kit lens may not be suitable so you might have to look at buying just the body and then finding the best deal on the correct lens.
I've seen some great shots done by people on proper low-rent cameras, and some crap shots done by people on £5K worth of gear. Unless he's already familiar with the principles of DSLR photography, then there's no point buying anything too fancy, as it'll just give confusing options when really it's not needed IMHO.
http://www.wexphotographic.com/digital-slr-cameras/b3065?sortby=1
Always good for prices when you do come to buy, and great customer service too. That's where I get most of my bits from these days. If there's something specific you want though, I can check duty free prices at the airport and am happy to pick something up for you if it saves you a few quid