With these specs, I might as well go dumpster diving and pull out a 1GHz thunderbird for free and install windows 95. That sucker would fly, and I'd get the memory protection and a descent web browser unlike what doesn't exist on AOS4, and all for free.
500 dollars for a 400MHz machine, no thanks. For 100 dollars more I can get a mac mini, which would freaking blow it out of the water.