I don't mind my OS using quite a bit of RAM, as long as UI elements are not drawn with HTML, and don't take as long to render as it would take to download a JPE

I don't mind my OS using quite a bit of RAM, as long as UI elements are not drawn with HTML, and don't take as long to render as it would take to download a JPEG on a dial up connection in 1995. Nothing in UI should take longer to draw than the human reaction time (~250ms). Most linux distros I tried pass this snappiness test with flying colors. Windows after Windows 7 don't. Besides, Ubuntu is just 1 distro. There will always be alternatives on Linux for lower resource usage.