First off, your links aren't working; I just wanted to see what case and hard drive you picked, so just tell me the brand/model. 210 for a case is really overkill, and that with the monitors eats up half of your budget.
Secondly, if you're only doing schoolwork, water cooling is really a waste of money. On air cooling, you can keep your PC quiet and cool easily. Only when you start overclocking to insane speeds will you really ever need WCing. It's also ridiculously expensive. If you're just thinking about your CPU, you could get the Corsair H50, but even that is a waste if you're not stressing the CPU. The stock cooler should be fine.
Thirdly, the CPU sockets are about to change, so you'll either be stuck with a current socket for a long time or you'll have to overhaul the mobo and cpu when you want to upgrade.
I would recommend an i5-760 + 4GB DDR3 dual channel RAM with a Cas Latency of 6 or 7 from a reputable brand (dunno what you can get there in the UK).
You will need a solid GPU for dual monitors (onboard video will usually not support 2 monitors, and it takes away more of your memory; depending on the resolution of your monitors, it can suck horribly). Even an older GPU like an Nvidia 9800GT or something can handle 2 screen pretty well.
A 500W PSU should do the trick (really dependent on your GPU). Aim for Corsair or Seasonic; they make the best.
The case was a Obsidian 800D but I guess I won't really be water cooling for ages so I won't need a water cooling friendly case.
I think I'll go for the HAF X as it's £130 and comes with a free gaming mouse at the moment.
Yeah, your case was overkill. Even the Cooler Master 932 is a bit much.
I would really consider a mid-tower like the Cooler Master 912 or 922, and the Antec 300. They're only $50 in the US (so ~50 pounds in the UK), which saves you more money and gets you what you need. I've owned the Antec 300 (before my current full tower), and I would honestly pick that case again if I needed another mid-tower.
The Samsung hard drives are amazing. Good choice. End of story.
The XFX PSU is more than your system will need, but it's OEM is Seasonic, which as I said before is the best in the business, so I would recommend it.
That 9800GT should work fine; even if you decided to play a game here and there it could handle it on one screen (probably not both).
That motherboard will work well with the i5. Asus is a very reputable brand (their customer service is difficult, but then again whose isn't these days) and you can expect it to last a good while.
I don't know much about Crucial or overclocking, but I'd imagine that memory is easy to overclock given its low stock voltages.