Hard Drive Partition

I have a 1000 GB Seagate Barracuda hard drive. Built my computer myself and am still working out the bugs in my abilities. But when I installed windows and ran the format, when it was all said and done. I only saw 127 GB of space. Thought, hey maybe it only shows that much on the my computer part. Other programs recognize the entire space of 1000 GB. So I was checking out partition software. Found one called EASEUS Partition. Works fine and all but I can’t resize C:/ to 500 GB like I want to. So my other option is, that I copied the C:/ drive and made it 500 GB. My question is this" If I delete the original C:/ drive and then rename the H:/ drive as C:/. Will this action crash my system? And will the computer allow me to perform this action? Help me on this one please someone.

You have to be a little clearer as to how you have it partitioned now.
Which windows OS are you using? If Vista, it comes with a partitioning tool called Diskpart. What other programs see the full disk? You cannot delete the partition you booted from. I prefer Gparted for partitioning tasks, you download an iso, burn it to CD which is bootable, and do the partitioning outside of Windows.

if i recall correctly, if your PC is older with a older bios it might have issues with hard drives larger than 137GB due to something called ‘LBA48’ not being supported.