Trouble trying to Restore Mini Mac

I recently acquired an older Mac Mini from around 2005. It is a 1.42 ghz powerPC. When I got the machine (3 days ago) everything worked great and it was running OSX Tiger. I upgraded the RAM to 1gig and it still worked flawlessly. I wanted to upgrade to OSX Leopard and while trying to upgrade I did something wrong and ended up erasing the entire Hard Drive. I didn't lose any data because the computer was only mine for a few days, BUT right now I obviously can't reboot because there is no OS on the HD. The disks I was given from the previous user for Tiger restore are copied disks...which haven't worked. Not sure if it's because they aren't specific to the machine or because they have a paper label on the top that prohibits them from properly rotating inside the drive.

I have done a ton of research and tried to install the OS from my macbook with the mini in Target Disk Mode connected by FireWire. When it asks for me to select a destination for the install, the Mac Mini HD has a red exclamation point with a circle. I'm not sure if I need to reformat the HD a different way, or if I need to reinstall from a Retail version of either Tiger or Leopard. I have the retail Leopard disk somewhere...I just can't find it.

Any ideas? - I would love some help!

You need either the retail version of Tiger or Leopard. Find the disk(s) or buy a new set. You can't install using Target mode because your MacBook has different hardware and the same version of OS X will not work with the Mini.

The copied Tiger disks are illegal and should be discarded.

Found a retail copy of Tiger and took care of everything.