Dell Inspiron E1505 Hard Drive replacment...Need step-by-step..Format first? or Load Windows XP first?

I just bought West Dig 320gb hard drive to replace my 80 gb that came with system...it's the Scorpio Black Hard drive...

In any case, I do not know what happens first...load CD from Dell with Windows XP?  Or do I have to do some sort of formatting procedure first?

Any sort of step-by-step would be a lifesaver!

Thanks!
Mike