Extending the boot partition on Mac OS X Leopard

I installed the Mac on my system on a 25GB partition. The other 75GB were allocated to Windows XP. Then, I got a new hard drive and installed Windows XP on it and erased the 75GB allocated to the previous installation. And knowing my luck, my DVD drive broke so I had to get a new one. The new one won't allow me to reinstall Mac and the current installation of it won't even read it. So now I'm trying to see if it is possible to just extend the Mac partition and give it the entire drive to operate on. I tried Disk Utility and Disk Studio on mac which didn't give me any options for the Mac drive. I also tried disk director on Windows to see if I can extend the partition but that was still a no go. The disk director says that the Mac drive already has the maximum amount of space which is complete bullsh*t. As far as I know, I have two options. Get a disk partitioning program that actually works for either windows or mac. Or figure out how to make my DVD drive to work.

P.S. I also have a CD drive that the mac can read, if it is possible to split the installation DVD into multiple CDs, please let me know.

Thanks

Do not delete the partition; there is a more efficient way to solve your problem.
And you are very lucky, I just got the useful information about extend boot partition, I can share with you.
My friend told me, Extend Partition Assistant Professional Edition can work well.
They often resize partition (extend partition, shrink partition…) through it, so, I can promise you--it worth to try.
This software has free edition, you can experience its superiority.