Hello Wizzard

I too have tried your game for a spin. You seem to have a lot of the basics covered already. Now it is time to refine. You say, it's completed. I dare say it's not. Take a closer look and see how complete it really is, as there seem to be quite a few areas that still need tweaking, before you can really say it's completed

Let's start from the beginning.
Your game has no options. Ok, that's understandable for a game of this size. But even so, imagine how you enjoy the (midi?!) background music, I myself find it horrible. It makes me want to seek out the midi options in Windows and turn it off. (well actually I dont, but I'm making a point here).
My point is, not everyone likes your choice of music. Make it so people can turn if off, or they will turn away from your game.

Be sure to test your game in Vista as well. I dont have XP at home anymore so I can't say for sure if it's the case on XP too(I assume its not), but on Vista the mouse disappears if it isn't near the border. Somehow it is visible near the borders, but as soon as I move it to the center, it disappears. It's very weird, I know.

Next one isn't mandatory, although it does help solve the problem Robert mentions. Use some kind of fade in/out when changing screens. It gives the player an idea of what's going on. Right now, I'm going from the main screen/menu to the game in a split second. One moment I'm listening to a familiar tune, the next it's instant action. It sounds good, but it really is not.

Then the game itself. It all looks very hectic. There's a lot going on and a lot of it is going wrong in some way or another.

You've got fighters moving from top to bottom, although they never actually reach the bottom. Moments before fighters get there, they suddenly disappear and apparently restart from the top again.

There are rockets going down the screen as well, but they have some kind of odd flicker during the animation.

Already mentioned by Robert, but collision detection does not appear to be pixel precise. This is especially apparent with the larger enemies. This makes out for a really annoying experience as you often think you're safe while you're actually not.

When I fire two or more bullets in a row and the first one hits an enemy fighter, all of my bullets are destroyed instead of just the one that hit the enemy fighter.

This one is really odd, but on some occasions, when I shoot one of the smaller fighters I immediately see a new fighter reappear. Usually a bit lower than the fighter that got shot.

You should also recheck the position of the planets. Currently they are drawn last, while they should be drawn first.

There's a few more things, but I think you'll get the idea.

Dont get me wrong here, as I do applaud you for getting this far. But the way I see it, you do have a few hurdles to cross before you can call it completed