I’m not too happy about the idea of archiving to harddisk although for practical reasons it might be the way to go. Buy 2*1TB disks. Duplicate everything and store the drives safely somewhere. I may consider Bluray too. At 25GB per disc it’d take a fraction of the time to archive everything.
A more pressing need is “current” space. Because of duplication for safety I have about 150GB of space on my internal drive. Looks like I’ll have to retire 2007 back to the external drives.