Windows 7 Install Partition Merge across 2 drives

[Ventral_Finn]

Hello!

  So my machine is a bit of a Frankenstein; my graduation gift from high school that has had literally every component but the keyboard and the chassis replaced in its eight years of existence.  6 months ago, the original hard drive was starting to give out, so I decided to get a replacement.  I put my fancy new drive in, installed windows 7 on it, switched out the drives so the new one was C: and the old one is D:.  On start, it takes me to a screen where I choose which Windows 7 install I want to boot, I pick the first one, and we're all good.  Unfortunately I can't remove the old one, because when I do, the machine stops recognizing that C: has a valid Windows 7 install.  When I first found this, I shrugged, put the old hard drive back inside, and thought nothing more of it.
  That is, until my angel of an IT guru blanched upon hearing the tale.  She took a look in my computer manager and found that the functions of the partition seem to be split across the two drives.  I've attached an image of the division of labor as described by my Computer Management program to this post.  I've also included a fresh dxdiag for good measure.  Is there any way to merge the install, such that I'm able to boot solely from the C: drive, and can remove the D: drive entirely?

  Thank you for your time 



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[Geek-9pm]

First things first.
Do you have a working backup plan?
Have you saved are your own relevant work, including e-mails and photos?
Do you have the DVDs needed to install all your programs again?
If so...
Second things.
Next, put out the old drive.
Do a full install of Windows 7 again.
Install drivers.
Get the updates.
Install programs.
Restore from backups your stuff.
Third thing.
You can get a enclosure to make your old drive into a backup device.

[Ventral_Finn]

I have most stuff backed up.  I can do the rest pretty readily.  As for the install discs, I can't seem to find mine, and might just need them shipped across the country if I was the chucklehead I think I was and didn't prioritize them in the move.  Whatever the case, I'll certainly give it a shot whenever I get my hands on the discs.  I was just hoping there was a way to transfer the relevant files from D: to C:, giving C: the whole set and letting me axe D: with impunity.  If nobody has a way of doing that, I'll take this path as soon as I'm able, and let you know how it turns out.

[Geek-9pm]

Well, thee is  another way. But what I outlined above is, IMO,  the more conservative way to fix the problem.
Do you w ant the other method?  If so, here is comes....
You get a suitable partition manager program and split the C: in to two partitions. Then use the tool to duplicate the old drive onto the new partition.  The tricky thing is to re assign the drive letters. That can ruin your day.  I have not done this ever, so I an reluctant to even suggest it.