Buying a new HD. Quick question

[GreenGrass]

my hard disks just died and from what ive read Im thinking of going for the: Seagate Barracuda 7200.10 500GB ST3500630AS SATA-II 16MB Cache
rather than the WD 500Gb and maybe slap it in a OcUK Silentmaxx Aluminium Hard Drive Enclosure. Is the seagate one of the best in the £180 price range?
also
Is there any advantage of getting 2 x 250Gb disks over just the one 500Gb?

Thanks

 

[GreenGrass]

ah right i see, thanks for that. Are the Hard Drive Enclosures any good, think I might go for two hard disks instead now. Do these things dramatically cut the amount of noise?