I see your boot manager is located on Disk 1 in Drive D, because it is marked as active and system. Apparently when you installed both Vista and 7 you had disk 1 hooked up to your computer and the installer put the boot manager there. Unfortunately, that really complicates things, because right now, I don't believe either 7 or Vista will boot on its own, without Drive 1. I also noticed that E partition is a Logical Drive and I don't believe it will take system files, unless it is converted to Primary like your other partitions. I don't know how comfortable you feel with making the changes needed to move the Windows 7 partition to where Vista is now located. If it was me, I would re-install Windows 7. If you unhook both disks 0 and 1 from your computer, then the Windows 7 installer will put the boot manager on HDD 2. When you boot up your Windows 7 installation disk beforehand, you can install 7 to your current C (Vista) partition and it will automatically install the boot manager on the same drive. Also, if you install to the Vista partition it shouldn't affect anything on the K partition. Just do not have the installer reformat the disk, when it asks if you want to do that. Also, since the partition already exists, Windows will not create the 100 Mb system partition, which you don't need, unless you use Bitlocker. Bitlocker is only available on Windows 7 Pro or higher and not Home Premium. Once Windows is reinstalled then you can hook the other two HDD's back up to the system. Also, will want to use Diskpart to make your D partition on disk 1 inactive, instead of active. I will see if I can find a tutorial to help you out. I would still back up K partition as a precaution, before installing Windows on the Vista partition.
Partition - Mark as Inactive
Note: If you need help reinstalling Windows 7, check out the tutorial section of the forum. If you still have questions, please feel free to ask.