Ricing is the act of modifying your car with not only no intention to gain performance, but also the chance at losing performance. Your car ricing to computer ricing analogy is WAY off base.
First, any overclocking that is actually increasing performance is the exact opposite of ricing. It is more like tuning your race car. Overclocking is also the most efficient way to spend your money 90% of the time. Second, I wouldn't even consider windows, fans, and other semi-useless mods to a case in the same category as ricing.
Here are things I would consider ricing:
Cutting blowholes into your case without putting functional fans in behind them (much like non-functioning hood scoops).
Excessive neon lights to the point at which you have to buy a bigger powersupply.
Fan placement that actually raises the heat of your PC by blowing the air into the wrong spots.
Placing stickers onto your PC with the sole purpose of making it look like a faster processor than it actually has.
Racing stripes on your PCB?
Things I would not consider ricing:
Windows: no matter how lame the window looks, it still serves the basic purpose of allowing you or others to look into your PC without having to remove the case cover. This is useful and handy.
Excessive fans: If the fans continue to cool down your PC, then they are serving a purpose. It is only a matter of noise here and if you can mind the noise then more power to you.
Overclocking: performance gains should never be confused for ricing, thats a complete oxymoron. Overclocking is all about pushing your current hardware to the extreme, much like professional racers have to push their cars to the extreme.