Need help identifying MIDIs

I'm not sure if this goes in this board, I'm new here. I extracted the music from the Playable Monsters WAD for Skulltag, the songs sound so familiar but I can't really find out what song is called what, and what game they are from. I'd appreciate it if someone could help, thanks in advance.

http://www.mediafire.com/?w33x3vqhsa874zm

Those are the MIDIs, in one ZIP.

1.MID from this ZIP is an old chestnut. The earliest occurrence of it in a WAD that I can think of at the moment is HEROES.WAD E1M1 (1995), but it's almost certain to be older.

15.MID is a pathetic remix of a song from the game "Tetris" for the original GameBoy, probably based on a real classic composition, but that's as much as I remember.

1 - CHRIS3.MID by Christopher Wilkins. Supposedly an original song, made in 1993. (5-08-93 to be exact)
7 - Donkey Kong 3 final boss music. http://www.youtube.com/watch?v=Mo6ZydM9rkg
17 - "A Field For Mag" from Tyrian 2000. http://www.youtube.com/watch?v=uOoJS06I3DI

In exchange, help me to identify this MIDI: http://speedy.sh/MYEuK/D-E3M2.MID
It was found by Walter on some anime related website but it might be from a video game too.

The one that I want to identify the most is 20.MID. I'll also try to help, Memfis. But if anyone could identify 20.MID and 16.MID in particular, I'd be very grateful.

20.mid is a song Downfall by Children of Bodom.

Thank you for the CHRIS3 ID, Memfis.

Nah, you should thank TGH for this info... or maybe even yourself. :) ("TGH might know what D_E1M5 is based on.")

16. is a song from Super Metroid.

Brinstar

A lot of these MIDIs are identifiable simply by opening them in a MIDI edtior and taking a look at the track names. :)