Agreed. For the average user, the absolute (yet impossible) ideal would be ambient, or room, temperature for all components. But shiny parts convert electricity into pretty pictures on the monitor, so that won't be happening.
Just flipping open my tmep monitors now, it looks like my CPU is at 20c, my motherboard is at 24c, and my video card is at 49c. But my room is kinda cold and I just turned the thing on. It's holding steady, but if I turn on a game everything will warm right up.
Which brings me to my next point. Want to cool your computer down? First step would be lowering the temperature of the room, but most people don't do this since it's not practical or comfortable. Second would be increasing airflow: bigger fans, cable management, etc. After that, you can start messing with VGA coolers, high-end CPU coolers, and so on, until you get into the expensive and dangerous water cooling, the ridiculously-priced phase change coolers, and lastly, pouring liquid nitrogen on your CPU.
The highest you want to go is really something like a Zalman 9700 on your CPU, and an aftermarket video card cooler, preferably one of the all-copper jobs. I use a Zalman 9700 and Arctic Silver thermal paste, works fine.