it makes absolutely no sense that my imac G4 800mhz 256 ram produces better display than imac G5 i5 with 4gb ram
The stats you posted on clock speed and ram have nothing to do with the display. Age doesn't mean much either. There are lcd displays built five years ago that beat the quality of the thunderbolt display today. Now they did cost more than the thunderbolt display, but my point remains.
it makes absolutely no sense that my imac G4 800mhz 256 ram produces better display than imac G5 i5 with 4gb ram
The stats you posted on clock speed and ram have nothing to do with the display.
Depends on what G5 but some of them used TN panels.
it makes absolutely no sense that my imac G4 800mhz 256 ram produces better display than imac G5 i5 with 4gb ram
It does on some iMacs. On the 20" G4 iMacs, the display display used IPS technology instead of the lower quality TN technology. I know that this difference is also true on the 20"/24" aluminum iMacs, possibly others.
Anyway the OP is confused because he felt that a later model should have a better display.