Unable to reset admin password cause I cannot boot up using CD

I'm having trouble trying to reset my admin password on my Leopard machine. I am current on all software updates. I purchased the system (desktop iMAC) last year from Apple with Leopard already installed. When I changed my password last week I failed to write it down and now for the life of me I cannot remember what I changed it to. Ok so no big deal (yeah right!) I'll just start up from CD and reset it that way. Well, I started feeling this wave of resistance unfolding and sure enough I run into my first instance of conflict when I hear the CD constantly spinning up and down for 5 minutes while I'm holding down the "C" key. Upon release of the C key the disk just kept on spinning up and down so I had no choice but to power it down using the on/off button in back. Upon restarting the system would not boot up as long as the CD was still spinning so I restarted again holding down the eject key then the CD ejected. So next I started up the machine normally and after it came up I inserted the Installation disk again and waited for it to appear on the desktop which it did. So I went into the start up control panel in system preferences and selected the OSX installation disk in which to reboot from. Same thing.
Disk kept on spinning up and down doing nothing. So I restart it holding down the option key and select the OSX disk and does the same thing spins up and down. I already repaired permissions and zapped PRAM and even looked for error messages when I started up using verbose startup. nothing looked unusual. Ok so now I am at the point to where when I insert the installation disk it shows up on the desktop I double click on the icon and it opens up to its content window but I get the error message: "You can't open the application "Install Mac and Bundled Software" because its not supported on this architecture". I'm not having trouble opening any other CD or DVD on my system. Heres my question other than the obvious one of not being able to run the installation disk to reset my password. I removed every language except the English language from each application the other day because I read that it would improve processing time so I removed every foreign language in my applications folder.
Do you think thats the reason I can't start up because maybe at when booting up from CD it looks for one of the foreign languages?..I don't really think this would have any affect on my problem. But I can't think of anything I changed including my password.

Can someone please share some knowledge.
Thank You Very much for your time and knowledge.

Mark

 

Hi I'm not too sure if I'm doing this right but I'm trying to send you a PM but I think I still may be ineligible to do so. In any event I am still having problems with my install disk.

You said that you have some information for me that would help me get out of this mess.

Please Advise. Thank You.

Mark