My favourites almost exclusively come from the NES as that was what I grew up with. I can still sit down and just listen to some tracks on youtube. I′ll list some games that have music I still enjoy.

https://www.youtube.com/watch?v=t6NpkRuLf2k

Batman

Return of the Joker

Ninja Gaiden (https://www.youtube.com/watch?v=zP_D_YKnwi0)

Shadowgate (all of them)

https://www.youtube.com/watch?v=scicO4v8d3M

Mega Man (https://www.youtube.com/watch?v=PAeIMQierX4)

Sega Mega Drive - Sunset Riders (all of them)

There′s probably more than this but these will do for now. So what music from old-school games do you still enjoy?

I have https://www.youtube.com/watch?v=zpVIM8de2xw as my ringtone

And even though it's fake, https://www.youtube.com/watch?v=wfvpNd56yrY is great too

A good one but I would have thought you had Gemini Man′s theme..

Yes, a reasonable assumption
But the way Snake Man begins makes it work great as a ringtone. Also applies to https://www.youtube.com/watch?v=Rv2Ju2gNGg0.
Alas not for https://www.youtube.com/watch?v=1buql896MM4.

And no, i'm not Gemini, i'm Libra

Oh, yeah! I forgot about this one!

Not according to your avatar, you aren′t

I'm here to hand out https://www.youtube.com/watch?v=5bf-EGuMfag. Let's get going.

This one reminds me of https://www.youtube.com/watch?v=-14W5XTqL5U from Street Fighter!

If I was in a coma, all the doctor would have to do is play the 8 bit Zelda theme and I would wake up

I regularly listen to game music from the 80s.

Some of the favorites
https://www.youtube.com/watch?v=qrQuR1LHAVI
https://www.youtube.com/watch?v=d5m6ODRUfUY
https://www.youtube.com/watch?v=WmC2nsPiMz4 (the morse code are the names of the 3 devs)
https://www.youtube.com/watch?v=tyyewEqUtAU (takes 2 minutes until the melody begins, but it's awesome )
https://www.youtube.com/watch?v=hiLvoMpLQFA (https://www.youtube.com/watch?v=MwnJBvfIboM)
https://www.youtube.com/watch?v=aKKNBjFz9XE
https://www.youtube.com/watch?v=0TKV_90aYgI&feature=player_detailpage#t=300s

And then a bunch of NES songs others will link anyway, like Mega Man 1-3, Castlevania 1-3 and Bionic Commando, and I did http://www.cdjapan.co.jp/product/COCX-38295 a while ago.

Streets of Rage and it's soundtrack is awesome, easily the game I've played thru the most times in my life. Even broken the highscore once, got over 999999 so it started over from 0 and finished the game with a very low score

Oh yeah, Rob Hubbard made some kick ass C64 tunes

And you can't speak of C64 music without https://www.youtube.com/watch?v=--pyo1r5luk And yes, it really takes that long to load games on C64 And then it looked it this: https://www.youtube.com/watch?v=94NSukbzwUQ
Games have come a long way since the 80's.

Monkey Island, The Neverhood, Grim Fandango. Great games and great soundtracks.

I never played the C64 version, but I did play it both on arcade and the https://www.youtube.com/watch?v=x3ITSQBdrhs.

Don't ask me why but the music to the very first dragon warrior game on nes. Also a shout out to the first metroid.

I still occasionally listen to and watch the intro to one of my favorite computer RPGs, https://www.youtube.com/watch?v=B4jsCt8T6Mc. I rebought the game last year at GoG and installed it, but due to prolonged illness never got around to playing it (or much of anything else).

The themes from the 3 Strike games that were on the Megadrive (Or Genesis for you Muricans').

(Favorite) Desert Strike:

https://www.youtube.com/watch?v=HnkXaLmYG34

(Least Favorite) Jungle Strike:

https://www.youtube.com/watch?v=ADvY1JYeOlU

(Second favorite) Urban Strike:

https://www.youtube.com/watch?v=Iknefj-NY3I

Only 3 childhood games that i kept.

Edit: Great, now i have to play Desert strike...........