Will the latest version of Mac OS run on old iBook

[quinnlaup]

Hey Guys

I am a relative noob to Mac OS i can find my about etc but dont know a whole lot about the operating system but i was wondering if the latest version of OSX can be installed on older iBooks. I am thinking of buying one for burning mac testing software such as tech tools etc and to familiarise myself more fully with the os. The iBook in question i believe has a 500mhz processor with 640mb of ram i think the os is 10.3.???? Also would i be right in assuming that the HDD can be upgraded from 10gb (i think).

kind regards

quinnlaup

P.s. I have had 2 of these in recently which when they heat up tend to stink really bad almost like body odour!!!! is this normal???