Total N00B Building a New Computer

Any comments at all would be nice!

Looks good, except for the motherboard. Get a good P45 board like this one

ASRock P45XE $94.99
http://www.newegg.com/Product/Prod [...] 6813157143

You will be able to add another 4850 for crossfire latter on.

what about this?: http://www.dabs.com/products/asus- [...] =405070000

The 4850 has a considerable edge over the 9800GT plus it has 1 GB of VRAM. Hands down, the 4850 wins. (Plus it's cheaper)

I'm unsure whether newegg ships to the UK or has a UK site

Better overclocking headroom. Plus, the 630i motherboard chosen requires a BIOS flash to support 45nm dual cores (and possibly doesn't even support it).

Thats a good board for the price. Keep in mind however that you will not be able to crossfire a second 4850 in future if you want to. Dropping down to a 550 watt Corsair PSU also wouldn't be a bad idea if you decide to stick with that board.

What does the term crossfire mean?

Crossfire is ATI's means of linking two similar video cards for added performance. Nvidia's version is called SLI. Heres a Wiki article regarding crossfire:
http://en.wikipedia.org/wiki/ATI_CrossFire

Note that for a motherboard requires at least two PCI-E x16 slots to allow Crossfire or SLI (the only exception is when using an open-ended x1/x4/x8 slot).
The motherboard must also have support for Crossfire or SLI.

Heres a link to ATI's list of motherboards which support Crossfire:
http://game.amd.com/us-en/crossfir [...] aspx?cat=2

Heres Nvidia's "widget" for SLI compatible motherboards.
http://www.slizone.com/object/slizone_build_mobo.html

Do you think my video card and monitor are reasonably well matched, it would be a waste to have one drag the other down. At the start I was planning on using this one: http://www.dooyoo.co.uk/crt-monitor/hansol-710a/ that was until I found out how stupid that would be

very well priced LCD monitor too at £80. Don't know what that is in dollars but very cheap.

I would not recommend that nforce 630i at all. It is a very lousy chipset. You would be better of with a p35 or better. I would look into an AMD setup though over that S775. No upgrade path with S775. I know you really did not want to overclock but if you get a black edition chip it is so easy. Just a multiplier change. A 720BE and a 790x or 790gx board in AM2+ or AM3 form is all you need. For you AM2+ and ddr2 would probably be cheaper. You might even be able to go with a bit older of an AM2+ chipset. Just check board manufacturer for compatibility.