This one is one of my favorites I've decided, there's a definite Western theme going on, and my (and most other peoples' by the look of it) first thought was the unused boss area in Dino Mines. I don't think they actually used new tracks for other mini-bosses but where else would this track fit if not the only western themed level in the game? I think this would be a really cool track to go with whatever mini boss they were originally planning and it makes me even more curious as to what they were going to do with that originally.
The second one I found was also a brilliant track and even more bizarre. Aside from certain elements that remind me of Scorch's Pit this feels completely different to every other track in the game and doesn't really sound particularly Spyro-y. According to the guy who uploaded it part of the track name said "Haunted Speedway", so whether that was just a name they gave the track afterwards or if it was another level they were planning I don't know. If I were to theorize (be warned this is going to be very out-there) I would say that if they were to actually make the Super Bonus Worlds rather than the one level they eventually ended up with, this could very well have been one of them. It's a very upbeat track and very catchy, and if it was like the final bonus speedway it could well have been something completely different and cooler than the flights in the other worlds. Either way there's some really great tracks and I wish they could have been included in the game.