I think 'Burning building' is a decent game. However I noticed some things that could be improved, which I'll list in order of how fast they could be fixed:
- The title would look more professional as 'Burning Building'.
- Falling objects don't seem to spawn outside of the upper screen border, resulting in them visually appearing out of nowhere.
- I'm a little concerned that there's no consequence to the player when he doesn't manage to rescue people from the building. I'm sure one of his colleagues will take care of the people he left behind, but there should be a fine of like 25 points or so. This would be an additional motivation for the players to rescue 'harder' targets.
- Players get a Highscore, but no Highscore board. This makes score pretty pointless to a lot of players. Newgrounds provides free boards for developers which you could use. Trust me: A Highscore board really adds some replay value.
- There is no curve in difficulty. If you play the game for a few seconds you already have seen everything the game is ever going to be... Now I'm aware that this is supposed to be a simple game, with easy to understand controls, but that doesn't mean it has to be boring. Since it's still in a very basic state, I don't want to meddle too much with your vision for it, but maybe you should try out different speeds as well as more variation in obstacles. Maybe even different levels where you could use different skins and obstacles altogether.
All this being said, the firemen topic and saving people really speaks to me. I like the topic, the simple controls, as well as that it can be understood by players of all languages and ages with only the tutorial (the arrows that appear when you first play).
There's pause and mute buttons, which far too many submissions here lack. You even went as far as adding separated mute buttons for BGM and SFX, which really is a plus. Still, the music is good and looking for mute wasn't my first concern.
You've created a stable basis and found a good topic to spin your game around, but there's still plenty of room for improvement. Best of luck!