As BigB suggest i would go for well known branded memory, i would also like to add to his suggestion that Geil would be a good choice, their range tends to be very expensive (as do most overcocking / performance memory chips) however if you go for their “Golden Value Range” their Value range actually out-performs the Corsair gaming memory chips, in terms of overclocking capability and stability.
I have 512mb Geil Golden Value PC3200 400mhz and i can overclock it with no extra cooling to 265mhz stable thats 533mhz (almost PC4000 or PC4400) and its very cheap, check out www.overclockers.co.uk for examples on memory..
Your graphics card should really be higher, if ur just using ur pc for internet / applications / music / videos e.t.c then thats fine, however i doubt you would be building a pc of that caliber (spec wise) ie a barton chip and that motherboard without the intention of some atleast mild gaming..
If u r into gaming, go for atleast a 9600XT (£80+), and i wouldn’t go with that Powersupply, i have used them before and they did not like my 2500+ Barton, i then switched to a 480Watt ThermalTake and it was fine 
Powersupplies i suggest: 400Watt or more from either: Antec, ThermalTake, Enermax, OCZ
And your hard drive is fine, however you can pick up a SATA (Serial ATA) version of it for maybe £3-8 more, and SATA is alot better than IDE / UIDE.
I think most people would agree on these changes:
PowerSupply/Case: 400W or more Enermax (Very Cheap But Very Good PSU’s) Or.. An Antec Case with Powersupply such as: SLB3700 comes with a powersupply 400W i think (i have an older one with a 350W running a P3 [email protected]/512mbSD133ram/6x50gb hard drives + 2 optical drives, and a graphics card)
Memory: From a well known brand or GEIL Golden Value range (cant recommend enough)
Graphics: 9250 is fine for older games, or standard applications, however if gaming i would look at getting a 9600XT 128mb, minimum really (u’d be fine with this), if possible a 9800SE (bout £8 more) or a 9800Pro / Standard
So you really should only see a price change because of the graphics card.. then u ahve a very nice system :good: