No, 10.6 will not work on ANY eMac. The eMac line never made the transition to Intel CPUs (thankfully) and 10.6 dropped all support for PPC CPUs. PPC systems, like your eMac reached the end of the line at 10.5.
I found some discussions here re: using Leopard OS with eMacs. Anyone know if Snow Leopard will run on a 1G eMac? I have Family Pack OS installation disks for 10.5.1 and Snow Leopard 10.6
Think they will run OK on eMac?