Raid 0 Question help

I have a new computer set up in a raid 0 confg. with 2 WD 120 meg
drives. I find if I try to use XP scan disk it stops and says Windows
was unable to complete the diusk check I suspect this is due to the
raid 0 confg. Is this correct. It also has a NTFS file system does
this mean Windows XP defrag tool will not work either,

Thank You

David Wells