Why even bother with a lap top? Do you need mobility? If so, you can plug in whatever keyboard and mouse you're comfy with and hook it up to your screen. This however is clumsy and you need a huge desk, plus you'll have wires all over the place.
That acer looks lovely. The i3 3220 is the chip I built Kyla's pc around, also with 4 gigglebytes. It's a lovely little machine and does everything she needs. She uses it for studying, browsing, all the usual stuff and it's great. The only thing I'll be adding at some point is an SSD, as that really does make a difference.
I've actually been contemplating starting up a little business on the side, building systems for people but I'm still a long way from that.
If however you'd like me to put some prices and lists together let me know. I've built so many systems over the last few months it'd be a shame to not help friends and family out.
Have you got the peripherals? The most important thing for you guys will be a nice if 24" monitor, perhaps even two if you're working on it. With 4k screens dropping in price now is the perfect time to grab some 1080p panels, you can pick up a £600 for a quarter of that.
If you do some considerable typing, you'll want a nice keyboard too. I recently got a Vengeance K60 mechanical board and it's so lovely to type on. It's just one of those things you go without for years thinking it's overrated but when you get it it all makes sense.