Replace a Hard drive in a array

I have a Dell Dimension 8400 with a Array of two 250MB disks set up in a Raid0 configuration, I'm having blue screens and disk errors always refered to disk 0 of the array.

I plan to replace both hard drives with two 1TB that I've already bought from Dell, I would like to have some help in how to do this, I know how to phisically replace the disks, also I have some information about creating a Raid1, (this time I want a backup), with the motherboard Rom Array controller.

I've already ordered a Win XP replacing CD from Dell, what I don't know is how to procced for the drivers and OS installation, I have a wireless keyboard and mouse, do I have to find a wired one for the installation? do I have to format the new drives? and which would be the installation order.

I would appreciate all the help from the knowledge people in this forum.

Thank you.

Raul.