help with HDD setup

[soul_child]

i've just bought 2 seagate 7200.11 500 gb drives and i currently have 2 7200.10 drives on my pc set up as separate drives containing the OS and games and appz.

I do the occasional gaming and web development and mostly watch tv episodes on my pc. I was thinking of using the 2x250 gb as backups and additional storage in a NAS enclosure, however i am not sure whether i should raid the new 500gb drives or just keep em as separate disks. anyone care to offer their suggestions as to how they would utilise the drives ?

thanks

 

[soul_child]

would it be advisable to go raid 0 on the 2 500gb and back up my entire disk periodicaly? how much space would i need to back up the array in case it needs rebuilding?

 

[soul_child]

thanks i think i will set them up as just seperate drives