Via two PAR codes, I've devised a way to beat almost any level (Excluding bosses, water levels, mine cart levels, and Slipside Ride which already has a warp)
1. Enter code 7E0EF380 (If that one doesn't work, try 7E052B09) and as DK, go to the leftmost part the level.
2. Hold B and you'll constantly jump higher and higher (Hold it for about 7 or so seconds)
3. Right after you let go, enter the code 7E16D502 and hold right (and Y to go faster). The screen should start scrolling.
4. If you have ZSNES, hold ` (It's above the "Tab" button and to the right of the "1" key on the keyboard) while holding right (The screen should start moving much much faster).
5. when the screen scrolls to the exit, turn off the code in step 3 and try moving left a little bit (because you could be standing on the exit), then hold ` again and you should fall to the floor within a matter of seconds.
Here's how it works:
The code in step one is "Moon Jump for DK", which makes DK keep jumping for as long as you press the B button. The code in step 3 is "Hover for DK" which makes DK fall down very slowly. When you hold B, you go very very high into the air, and when you turn on the hover cheat and hold right and Y, you glide right to the exit. Holding the ` key in ZSNES makes the game go about 4 times as fast for as long as you hold it ("Fast Fowarding" it) which makes you zoom through the level really really fast. When you get to the end, holding it makes you fall faster, so that if you are still really high up because you held B down to long, you'll still get down fast enough.