I fiddled with that idea before. If it is only for menu screen, then I suggest a tiled background covering the whole screen.
Now, you can make it scroll over time, using offset of the tiled background. Be creative; use sine movement, etc., I ended up making the starfield move around gently as if I was looking around.
Also, there is Perlin Noise plugin by Arsonide, if you want more "random" stars, it is not difficult to use. You can use the same seed number to generate same stars, too.