British newbie general purpose system

Thankyou very much for looking. I would really appreciate your advice. I am keen to build a reliable and long-lasting system for home use with plenty of storage.

Approximate Purchase Date: this week


Budget Range: £850 approx


System Usage from Most to Least Important: web browsing, writing and editing documents, running Napster via Sonos music system, basic picture editing in Photoshop essentials, watching movies, perhaps son trying out a game or several....


Parts Not Required: None


Preferred Website(s) for Parts: Any UK site if possible, but scan.co.uk o roverclockers.co.uk look hopeful.


Country of Origin: United Kingdom


Parts Preferences: No particular preferences. Enough room for a biggish case if needed. Silence not essential.


Overclocking: Unlikely


SLI or Crossfire: No


Monitor Resolution: Would like a decent monitor


Additional Comments: newbie, relatively time poor, keen on reliability above all and keen to keep system for some years if possible +/- new bits. I'd like to have generous storage on hard drive. I've been reading around, including a new book called Build a Better PC, and wondered about the following (prices include VAT):

Processor: Intel® Core i3 540

Motherboard: Biostar TPOWER I55, Intel P55, S1156, PCI-E 2.0 (x16), DDR3 1333/1600/2000, SATA 3Gb/s RAID, ATX (clearance price £110.43 at scan.co.uk, recommended by Build a Better PC)
Power supply: BeQuiet Dark Power Pro P8 650W Modular Power Supply £109.99 (overclockers.co.uk, recommended by Build a Better PC but looks as though it might be considerable overkill)

Memory: Corsair Memory XMS3 4GB DDR3 PC3-12800 (1600) Dual Channel Desktop
CMX4GX3M2A1600C9 - 4GB (2x2GB) Corsair XMS3 DDR3 PC3-12800 (1600), Non-ECC Unbuffered, CAS 9-9-9-24, XMP, 1.65V (no particular reason)

Case: Antec 300 Antec 300 Three Hundred Ultimate Gaming Case - Black £50.98 (overclockers)

Hard drive: 1TB (1000 GB) Seagate Barracuda 7200.12 Hard Drive - HDD
1TB Seagate ST31000528AS Barracuda 7200.12, SATA 3Gb/s, 7200rpm, 32MB Cache, 8.5 ms, NCQ £42.88 scan.co.uk

Graphics card: ?None to begin with at least - integrated graphics on card

Monitor: BenQ G2420HDBL 24" Widescreen LED Monitor - Black [9H.L3XLB.QBE] £164.49 (overclockers, recommended in magazine)

Operating system: Windows 7 Home Premium

Speakers:
Creative Labs 2.1 Speakers RMS Sound System 51MF0355AA003 - Creative Inspire A200 Speakers £22.30 scan.co.uk

If you can help I'd be very grateful, even if your advice is that I am clearly not suitable to build a system and should just go get a Dell!

Ben