Because it is simpler than posting and changing the parts one by one I'll just post what I'd go for given the budget.

If considering overclocking then it may be worth getting an aftermarket cooler such as the Arctic Freezer 7 but the stock cooler would do for just now.
Lian Li C-01B Aluminium CD-ROM/DVD-ROM Bezel (Black) £7.99
(£9.39) £7.99
(£9.39)
Lian-Li PC-7 PLUS Aluminium Midi-Tower Case - Black £49.99
(£58.74) £49.99
(£58.74)
Samsung SpinPoint P HD160JJ 160GB SATA-II 8MB Cache - OEM £36.49
(£42.88) £36.49
(£42.88)
Gigabyte GA_965P_DS3 (Socket 775) PCI-Express DDR2 Motherboard £69.99
(£82.24) £69.99
(£82.24)
Intel Core 2 DUO E6300 "LGA775 Allendale" 1.86GHz (1066FSB) - Retail £109.99
(£129.24) £109.99
(£129.24)
Pioneer DVR-111BK 16x16 DVD±RW Dual Layer ReWriter - (Black) OEM £18.35
(£21.56) £18.35
(£21.56)
OcUK 2GB (2x1GB) PC2-6400 800MHz DDR2 Dual Channel Kit £123.99
(£145.69) £123.99
(£145.69)
HIS ATI Radeon X1950 Pro ICEQ 3 TURBO SILENT Heatpipe 256MB GDDR3 TV-Out/Dual DVI (PCI-Express) - Retail (H195PRQT256DD-R) £112.99
(£132.76) £112.99
(£132.76)
Corsair HX 520W ATX2.2 Modular SLI Compliant PSU (CMPSU-520HXUK) £59.99
(£70.49) £59.99
(£70.49)
Sub Total : £589.77
Shipping cost assumes delivery to UK Mainland with:
City Link Parcel Next Day (Delivered Mon-Fri)
(This can be changed during checkout) Shipping : £10.95
Vat : £105.13
Total : £705.85