The text is pretty bold and not interesting at all. You should check out www.dafont.com for better ones.

The blood around the text could be extended to the background and should be more blood like and less like red paint brush. Try to use the regular brushes in gimp but combine them to get the nice look of blood splatter. If you can't get the effect you want, you can do your own shapes of blood from other picture (section, makes everything in red and copy-past it in your wall)

You should clean the coat of Alucard a lot cause we can see the crosses of the scan...
About the scan you also have a little problem with the extraction... There is white outlines all over the character but on some parts it's bigger than on others. You need to get the same thickness of outline everywhere. Or you need to remove all the white outlines on the hair and the hat... :-s

Note that using a black and white background simple is pretty hard. Especially when the character you use is in dark grey scale. If I were you I would use a really dark red background with some pattern or design and maybe use also the white stripe on the side? Don't know...

Last little detail. Your wall is in a really small resolution. Don't hesitate to make the wall bigger to fit more desktop ^_^

Anyway it's a nice start...

And good luck for the rest of the wall! :)