Here's the story...

My room mate decided to download an illegal torrent of osx 10.5 (my Mac was running 10.4.9 just fine) and tried to install it and got frustrated. He found a web tutorial on how to back up your drive using the Disk Utility restore feature. He "figured" that if you can copy your existing data from your HDD to another media why wouldn't "restoring" the illegal 10.5 image onto the HDD work... Well long story short, it didn't work and of course he didn't tell me what was going on until after I got back from my Thanksgiving break. The computer now fails to load OSX (Stays on the Apple screen with the rotating circle of lines forever... seriously it's been going at it for a few days.) Will not boot in Verbose or Safe Mode and the original restore/install disks are long gone. I'm not sure how to get my machine back up and running.

I do, however also have a G4 Tower running 10.3 that I had networked to the main Mac as extra storage and stuff like that. If I hook the two computers together VIA firewire and do the startup key combo to start off a target fire wire drive will that do anything?

Or do I have to buy another legal copy of OSX and install?

Any help is greatly appreciated!

If both macs are power pc's you could use carbon copy cloner (google it) to clone your g4 to your broken mac via firewire just make sure to back up your things first (also via firewire). In the case that your broken mac is intel platform I would just find restore disks for the same model and use them (do an archive and install) so that you wont loose any personal info.