I have yet to discover how people react to threads being bumped, but I assure you that it is with (hopefully) sound reasoning in mind.

Here is what I am thinking...
I would like to backlight buttons with a solid (not necessarily bright) orange.  I'd like the d-pad, start/select, and A/B buttons all to be illuminated and to have t he resulting color look similar/aesthetically pleasing when paired with a V5 Pumpkin backlight.  I am about to purchase some buttons and was going back and forth between plastic and silicone.  Several posts ago, it was suggested that I look into silicone, but I'd like some additional input if possible.

I would think that silicone would diffuse light more effectively, but I'm not sure whether I'd want them in orange or clear to get the right effect.  I'm also trying to keep in mind how the unit would look when powered off.  I know that's when it will be least impressive, but I want to avoid pastel colors (which is certainly the case with the solid orange).  Hence, I am leaning more towards clear.  However, if the orange would look extra good backlit, then I would be open to the idea.  However, I'm not even sure if the solid orange will be translucent enough to let any light through.

As for plastic, I like that they come in clear orange.  It seems it would not only color the light nicely but would also look nicer when powered off.  My concern with plastic is that I don't know how well it might diffuse the light from the LEDs.  Ideas?  Thoughts?

I don't plan on tackling this for quite some time.  I am hoping to make some obscure/unique DMG mods to see if there's a market for them, but there are things I want to make sure that I either already know how to do or could conceivably learn in a pinch.  Backlighting buttons is definitely one of them (even if just for the fact that I want to do it on one of my own GameBoys).

Also...

That GameBoy O____O

Also:

Which I made for superbustysamuraimonkey.

If you are trying to backlight buttons you might want to consider the clear silicone ones, since i think that is why they were made.

Also, thanks for all the good info, everyone.  I have an NES controller I eventually plan on adding LEDs to, and this thread should be useful with my lack of experience doing such things.

When are you planning on attempting this?
Also, don't stress over soldering, I used to concern myself with the idea of breaking parts… It just creates more problems.
No, you shouldn't require a resistor for the power LEDs or any if the LEDs you will use in buttons.
If one is needed for the power LED it should be included in the purchase from Nonfinite.

I've had plenty of experience soldering in the context of fine metalworking, but not in the case of electronics. Given my lack of experience, I'm nervous to solder anything ambitious (or anything at all for that matter) just because I've never tried to before. I guess like anything, I just have to try and fail a bunch.

Another turbo noob question: would I need to implement resistors into his LED venture depending on the color? I haven't seen any mention of such a thing, for example, on the listing for replacement battery indicator LEDs in Nonfinite's shop, nor anywhere in this discussion thus far. I don't want to leave anything important out!

By the way, thank you so much for the support, everyone. It's refreshing and very much appreciated.

A lot to get the LEDs right, hardest part is placing them. and soldering skills I guess

Acetone is used in Nail polish remover.
So any nail polish should work fine
Before you use nail polish I suggest you sand the buttons... It turns out much cleaner that way.

using the rectangular types of LEDs and laying them flat so they shine directly at the buttons works well also,

like these:

with a little hot glue they hold well, and are typically something like 2x5mm so not a lot to trim away in the case at all.  you'll need to cut away a little at the circle guard around the dpad area, and the A/B buttons, the s/s buttons though are open are ready for whatever you throw at them

ALSO!

if you want to get this mod up off the PCB, you can attach the LEDs to the case with hot glue too.  to avoid hotspotting on the case, use electrical tape and put it on the case itself if its a solid color and you can't see it, or if its a clear case apply it to the side of the LED (one of the larger sides) which would be facing you or against the plastic.  if you happen to have reflective tape you could use that too and regain some of the lost light.  just don't tape over the tip of the LED or you've defeated the mod

there are a lot of ways to kill the hotspotting, but this worked well for me (although it was a while ago).  electrical tape holds well over time too.

you could also use multiple layers of paint if you wished, nail polish even (eh, on second thoughts, i'm thinking its acetone-based, right?  or not?)

To install the leds for buttons?
I would suggest SMD LEDs if you are comfortable with soldering to them.
Any LEDs will work though.
You just have to place them near or in the button, I know a few people who drill holes in the button to sit the LED in.
Give the best result in my opinion.
Also I suggest powering the LED(s) from a different location than the backlight... In my early tries it caused dimming or flickering of the backlight.

Given my extremely (and I must stress 'extremely') limited knowledge of electronics, what all would that entail?  I know it's probably a question that warrants a bigger answer than a single sentence, so don't feel compelled to indulge my utter noobery.

Lights aren't a bad idea, though.  If you're going for a specific color scheme and are planning on using a backlight you can find LEDs that match the backlight--whether it's colored or simply white.  Then just use clear buttons.

Haha, I just wanted to post that one

Indeed, it's just painted. The bubbles appear because I used low pressure paint which I sprayed close, and a lot
There might be a bit of glow in the dark paint in that one as well, can't remember. That stuff gives mad bubbles

But there are no lights. Just a gradient of bright colours.

You might be able to see them better if look at the full size picture.  I believe it is just green and yellow paint with bubbles in it.  That added touch has me wanting to try the same thing for maximum bubbles in a set.  Timbob does some really cool stuff.

That is a damn sexy GameBoy...
I can't tell--are the buttons illuminated?  Or is the paint just so vibrant that they appear to be glowing?  Either way, that's delicious.