TIFF works too, if you were to upload it to imageshack saved as that file, it wouldn't have the color darkening a png does. Its also a smaller file then a bmp, but slightly larger than a png.
Anyways, overall the background is pretty good, but the car lacks a door. The window looks like it extends all the way down to the bottom.
I dont like how the main character looks all that much, he looks too big compared to the backgorund. Maybe you should try something similiar toCastlevania
for character anatomy. Overall its not bad.