u/Independent-Mess8780

Deep house, I think. No vocals. Similar to "Sweets - Fox Stevenson" in terms of structure. That song, along with "Bullit - Watermat" were probably trendy around that time also.

The song features a simple lead melody, which is constantly looped. Somewhat hypnotic. I can't recall the instrument other than that it was a hard synth, vibes or mallets of some kind.

Here's a quick sort of attempt at remembering and recreating the loop. Idk about the bpm, key or instruments though.
Quick midi recreation

After repeating a same few note sequence multiple times, the song would switch to a short bridge which sounded far more 8bit-y and NES like, before looping back to the same loop. This bridge also sounded like an upward scale sort of thing and was very abrupt and different from the rest of the song.

This is going to sound so vague but I'll try my best.
Probably in around 2004 to 2005 I was playing a little videogame on my school computer. I was a toddler. This appeared to be an executable file, not something I played online.

It was a collection of minigames, really. Something similar to "Purble Palace" but not quite. The only thing that comes to mind is crayons. The icon of the game might have been crayons also. I don't remember anything else, but I bet I'd recognize it if I saw it.