I don't really know much about Java (I've used it a very little bit once, buut nothing much), but I guess I'm starting to know this and that. Right now, you're probably using the GDI's Canvas for drawing the game... Now, the GDI is very far from the hardware, so you need to get through many layers of software to really do the thing you want to do. Which is all computed by the CPU. Furthermore, your images are stored in system memory, instead of video memory, so your CPU will have much idle time while the images are send from the system memory out. Hence why you should change to DirectX or OpenGL, othervise your game will slow in like HELL when you draw many pictures, and especially when you do blending effects (let's even not talk about additive drawing or things like that).
I'd also recommend changing to C++ or maybe Delphi, cuz Java is kindof a script language, so it could run much faster on those
About the what to do next part, I'll just write down how I've developed FS2D. I've first done the menu, toplist system and the score file encripting algo. Then the base of the scripting engine. (like preformating, and the layers of the handling and storing objects of events and cycles) Then the loading system that will examine the level and load the needed things from the definition files. Then the ship displaying, then the hit detection and health and shield handling and shield effects, then went to explosions and ship deleting. After that I've done general object handling and display, then made the diff classes for the diff types of objects and added their unique things. After that I've went to the bosses, but as your game's diff, I guess you handle those about the same as any enemy
After that I went to the special effects like lens flares and whatevers... and last was the scoring system, although it should've came before, but hehh, I was lazy
Hope this gave some help...
As for images and videos, I think you should use imageshack for images. It's veeery nice. For videos, some simple file uploader would be best, like rapidshare.de or yousendit.com (fake e-mail, shows the link).
Question about the game: How do you handle hit detection? (Hitboxes, the whole picture or pixel by pixel?)
oh, yea, and lastly if you'd like to make a glowpoint, drawing a simple sprite additively could nicely do (When you add the colour values of the picture to be drawn on the parent. It looks... glowy!