1. You cannot convert a native binary back to readable source code. There isn't enough information left and you might be able to just get back incoherent, partially inlined functions with randomly generated variable names and almost no structure. You won't be able to use the code in any meaningful way.

2. If this is not about decompilation but about game programming tutorials, then don't make the title of your thread "decompilation request". Now developing for consoles is not as easy as developing for PC since they are usually not open platforms, and I recommend you start with the basics on PC before going for console development. In any case, this thread will be likely moved to one of our technical forums where you should hopefully get more guidance.

3. Please don't post the same thread six times. If your internet connection screwed up after posting, don't just spam the "post" button, check if your thread made it and then try to post again if it didn't.

If it's not too late, you can usually recover deleted files with some sort of undeleter. I've personally used piriform's recuva. Perhaps you might be able to recover some (or all) of your source files.

EDIT:

Also, backups. Have them.

Or source control. SVN or GIT, or what have you.

You can decompile it ... prepare to spend many weeks translating the mess that results.

How did it come to be that you didn't have any copies of your own code, and a friend was responsible for preserving it?

Too late now but for next time, get yourself a Dropbox (etc) account

Did you get any information in your old Dreamcast thread to get you started doing homebrew for it, or at you still at square one?

I think it was a mistake making marijuana legal in Colorado. Who blamed whose mother for what? Got no source control and no backup, and want to develop for consoles?

How did it come to be that you didn't have any copies of your own code, and a friend was responsible for preserving it?

Too late now but for next time, get yourself a Dropbox (etc) account

Did you get any information in your old Dreamcast thread to get you started doing homebrew for it, or at you still at square one?

You'd be surprised at how common it is to lose code to early projects.

I've lost the code to most of my early games, old floppies that no longer work properly, crashed harddrives, misplaced backups, the list goes on.

The OP is talking about games that no longer run on Windows so they're likely to pre-date dropbox :)

How did it come to be that you didn't have any copies of your own code, and a friend was responsible for preserving it?
Too late now but for next time, get yourself a Dropbox (etc) account

Did you get any information in your old Dreamcast thread to get you started doing homebrew for it, or at you still at square one?

You'd be surprised at how common it is to lose code to early projects.

I've lost the code to most of my early games, old floppies that no longer work properly, crashed harddrives, misplaced backups, the list goes on.

Yeah, I've lost a tonne of old stuff. HDD failure, forgetting to backup before formatting, dropping floppies into drains... But that's all my fault/accidents; I'm not blaming/insulting my friends for not keeping backups of my stuff

But who is Casper, and what's his mom got to do with it?

It never ran on Windows? Or it doesnt run on current Windows OS?

If so, you can try install old windows versions on a virtual machine to see if the executables run?

At least you could record a video of your games you know...better than nothing >_>" I cant imagine the pain