The height of the sig is over the sig limit that we have at the forums (600x200 pixels). Change that and the sig would be acceptable. As for quality of the sig, there's not much of that (sorry to be so harsh!). The text doesn't blend well with the picture, the picture is low quality, and the background needs something wholly to be desired. I'd practice some more.
I think you made a good choice for the font. It's a little difficult to read, but it has a very eastern calligraphic look to it, which fits very well with the samurai theme. I'm also a big fan of Chrono Trigger, so you get big points from me for that. However, there are some things to work on. The outline on "Neo-Samurai" corrupts the look of the font, either get the outline behind the fill or try a different effect. I also think that the way you have everything arranged now leaves the right side very unbalanced visually. You might think about moving things around a little bit. Lensflares are fine and all, but I think in digital art they've been abused to the point that they should only be used when absolutely necessary. You did a very good job for the first time, just keep practicing as others have said. Always practice.