Hi everyone,
I've had a plan to play (and hopefully document/record/stream) all the Pokemon games, from start to finish. I've been doing research into how to do this, and before spending money I thought I'd run it past you guys, just in case someone spots an issue or has a better idea.
It's simple enough to get the video from an N64/Gamecube/Wii. I'll be purchasing an Elgato Game Capture HD to do this.
The main issue is recording Game Boy games. My current plan is to purchase a Game Boy Player for the Gamecube and play GB/GBC/GBA games through that, and capture the output from the Gamecube. Does anyone have any experience with this? I did own a Game Boy Player as a child, but I no longer own one.
I've heard that as long as your GC region and your GB Player disc regions are the same, it'll play any region GB game? e.g. my UK Gamecube, UK Game Boy Player and UK Game Boy Player disc can play Pokemon Green (Japan only).
If this does work, has any had any issues using the Game Boy Player? Any emulation issues etc. would be great to hear about. From what I've read, however, it's hardware emulation, so it should be pretty good.
As for DS games, if it got to that point, I'd purchace on these: http://www.3dscapture.com/
Any comments/feedback/ideas?

Well GBA games are region free, they'll work on any device that will play them. Also, not to insult your intelligence or anything, but be sure to use component cables to get the best possible video quality. 480p looks way better than 480i, especially on a monitor or other similar digital display.

Not worry about insulting my intelligence I'm here because I know I don't know enough about this sort of thing!
I was aware of there being 2 different cables, and I think I might own one. I have a non-standard cable for both my N64 and Wii (I know the Wii one is component, but I don't know if it works with a Gamecube), so I might try and figure out if they're outputting 480p.
Thank you for the reply!

The Wii one won't work with the Gamecube. I'm not too knowledgeable on the subject, but I know N64 and Gamecube use the same video out, for composite anyway (480i or less). Fairly certain the N64 can't do 480p, some even only do 240p.

I did purchase an "EasyCAP", but found it wasn't that great (I think I got a dodgy Chinese ripoff), but the quality doesn't look too bad.
I'll take a look at getting an S-Video cable for N64/Gamecube and capture that. It's not a huge risk since it'll probably help with Gameboy capture anyway, and if it doesn't work for N64 that well...

Well I have a GameBoy Player and an Elgato EyeTV Hybrid USB stick for my MacBook. I found it works best to get splitters to split your video signal so you can send one to your computer for recording and one to your TV for playing. Strictly speaking my TV is a gaming monitor, and I could just input the signal to my Elgato and then output it from my laptop to my gaming monitor, but I prefer to try to reduce any possibility for lag as much as possible because it can really affect your gameplay.

It's probably a matter of opinion whether component is worth the insane price the GC component cables sell for, though.
Also, if you're looking for the "best" quality, note that the first-gen Pokemon games supported the Super Game Boy for the SNES. SGB features will only work on a SGB.
(the game used SGB mainly to give each Pokemon a single color, but most helpfully it would color the HP meter yellow or red to indicate low health)

I'm still trying to source a Game Boy Player (I had one on eBay, but it messed up and I didn't win it ), so my progress has been delayed a bit

My monitor only has DVI, VGA and HDMI, so I don't think I can plug it in directly from my N64/Gamecube. The Elgato Game Capture HD is advertised as "Lag-free HDMI pass-through to the TV", so I'm hoping it'll be fine to just use the HDMI output

I have seen the SGB, but I don't own a SNES and because (I think) it's software emulation, I'd rather go for the hardware emulation in the Game Boy Player.
As for the component cable, they are very expensive, so I'll see how the quality is when I end up getting all my hardware!

The Super Game Boy does indeed contain real (monochrome) Game Boy hardware.
(Emulation wasn't even capable until the next generation. Such as Williams' Arcade Greatest Hits, they wrote emulators for the PS and N64, but had to write ports for the SNES and Genesis. For games a decade older than the Game Boy.)

I've heard Pokemon Stadium for N64 had a Game Boy emulator, though (designed specifically to allow Red/Blue to be played after loading the game through the Transfer Pak).

But if you're not inputting an HDMI signal to the Elgato, it's going to have to convert it to HDMI, so that won't be lag-free. The lag probably isn't bad if it's meant for gaming though. I suppose even on my gaming monitor it has to take the analog signal and rescale it and what not, so even that's not as lag-free as viewing on a CRT TV would be. If you still have a CRT TV, best case would be to split the signal so you can play on the CRT and record the second signal separately, but that's probably totally unnecessary if you're really just going to play Pokemon as I doubt a bit of lag affects that.

I finally ordered a (very good condition) copy of Pokemon Green yesterday, so I should be able to start my "quest" soon!

I do not own a SNES, and since it'd only get used to play Green, Red and Blue, I think I'll look out for a Gamecube Game Boy Player for now, but get a Super Game Boy, should one cheap enough come along. I have Pokemon Stadium and I've used the emulator, but (and you may prove me wrong again) I think that's software emulation, and I'd rather go with HW emulation wherever possible!

Yes, I agree that the conversion process could take a bit of processing time, but as you say, the lag will hardly affect a Pokemon game, and I live in student accommodation, so I don't really have the room for a CRT. I think there's an old one in the kitchen though, so maybe I'll use that when it's available, if I see a bunch of lag!