Macbook Upgrade

it seems like its time my macbook got an upgrade.  Its circa 2008/09 core 2 duo, and is still on leopard. I'd got used to using iPhoto for my basic photo duties, importing, raw processing etc. But it doesnt support the raw files made by my A65.  This seems a little odd, given that its the same suffix as the raw files from my a100, of .arw.

The question is what next?  Stump the money to order snow-leopard and then be able to upgrade to lion, or do something crazy, like convert it to ubuntu (thanks Jon for the idea!). Picassa supports the new raw files, and runs natively on OS X, so perhaps its a bit of a solution looking for a problem, and I just need to have a propper tidy up of the disk, as files have accumulated over the time I've been using it