QUOTE
I may have to upgrade my Mac just to keep up.
If you can run Snow Leopard, I highly recommend it. If unable to run that one, Leopard is worth it, also. OTOH, I'd recommend selling the Kindle, prepare to sell the oldest Mac you have, take in washing for a couple of months and then buy a new iMac!
Snow Leopard requires an Intel cpu, won't run on a PPC. Those apps must really be something if their keeping you away from Leopard!

QUOTE
what I've asked for for my birthday
What?! Are you still having those things?!