[X-Newbies] Your opinion on updating my OS

[greered at appstate.edu]

Hello -

I am looking for opinions on updating from 10.4.6 to whatever on my maxed out 1.42 GHz eMac.

Everything is working and I have a lot of stuff I really don't want to break, some of which I would probably have 
to pay dearly to update/upgrade.  I have a silver powerbook that I can play with if I want to test but hate to break 
it also since I do a lot with it, but I could.

What are your benchmarks for determining if/when you update your system?

Thanks,

Edward