Need partition help on my newly installed 5t hdd

I put a clean install of Windows 7 Professional on a brand-new 5T drive, and am now stuck with losing 607 Gb of space, due to my uninformed choices of MBR, and while installing the OS I made 2 partitions - one for the OS ~1T, and one for programs, also ~1T.

Thinking that I'd be able to make more partitions after I got the OS installed, I went on with the process to a successful conclusion. However, when I tried to make more partitions on that drive I got the message that I would lose the 607 Gb above the 2T limit.



Because the disk is MBR, and the 2T limit plus only being allowed 4 partitions, the partitioning software will only allow my to make one more partition - thus the message about losing ~607 Gb.

I have tried extending the C: partition, but for some reason I am only given the choice to shrink it because the software is showing 0 b available before or after the C: partition. No option given for extending D: since it's not up against any free space.

I'm wondering if this will work: Would I be allowed to delete partition D: and then make 2 new partitions out of the resulting 3.7 T of allocated space?

The only other choice I'm thinking of (other than deleting the OS and starting over) is questionable:

Can I safely merge C: and D: partitions without danger to the OS on C:? That should allow me to make 2 more partitions, right? unfortunately that would make the OS partition quite a bit larger than it needs to be, so I'm not in favor of it . . .


I've read all the tutorials here and other folks who've had similar trouble, but found none exactly answering what I need to do.

Thanks

Disk managment. I'll post that as soon as i get back to my pc. My op has a screen shot of all the partitions on the one and only disk. Is it not clear from that screen shot what I'm describing? Not sure why you're asking me if I'd be happy using only 2.2T, since my original post includes a picture showing my three drive using over that, and my op also states I'm trying to not lose 607 Gb by making the last partition 2.2T - meaning i have access to ~4T now. Using Partition software. Isn't my op clear?

I have - now - the ability to make a fourth partition - which, because of the 2.2T limit means I will lose the ~607 Gb, as mentioned in the op. I've got access to over 4T because I am allowed up to 4 partitions - which is why my op details that, and asks if the changes I proposed would be a good way to have - 1) the 4 allowable patitions, each being under the 2.2T limit and -2) save the ~607 Gb from being stuck as unallocated if I were to just make a new partition without first correcting the original partitions - and without losing my OS in the process.

Really - all there in the op. Sorry it confused you.

here is the screenshot from Dis Management you asked for -