i bought a ti powerbook 500mhz over the summer for school... once I can get a copy of 10.1 I was thinking I would format and re-install everything. From the factory my computer came with a 30 GB hd with i guess 2 partitions.. 1 for 9.1 and the other for X. To re-install everything after formatting what do I have to do? Which disk do I use? the 9.1 or the 10? Also, being a windows user all my life, i just realized I don't even know how to format the harddrive on my mac... Any help would be greatly appreciated.