Materially speaking ... Dual core processor usage?

It is unlikely that you have two hard-drives in there, so C and E must be the same hard-drive, but two partitions. I guess E is used for storage space, (independent of the drive you use most C, where you windows and program files are, including your My Documents folder.) for data security. And you can use it just like any other drive. Check to see what the size of E is. You are the one that chooses what will be placed in the other drive, or you can stipulate to what ever program to store there.

BUT. E also could be one of the new drives (like a floppy drive) for memory stick and cards (not a usb flash memory stick) like the ones for cameras or like Sony uses.

If you move any program files, it would be better to re-install the program to the E drive (if in fact it is a partition of your hard-drive), than to just move the folder to E (Because it will mess up any association with windows if the program is dependent on other files in the Windows directory, since windows will regulate that.)

PS if you are using Vista make sure you update it to Vista SP1 which you can find for free on their website.

The 'Dual Core' bit does not refer to the hard drives.

What you probably have is one hard drive partioned into two.

You can check by going into BIOS (F2 when you boot) and seeing how many hard drives are listed there.

Don't move program files from their installed position. They may not continue to work properly.

Drive E: may be used for data files (photos and such) OR your system may have a backup utility which copies all of drive C: to allow for an easy restore. If this is the case don't rely on it, as if your hard disk fails, you may lose the second partition.

You are confused

They are hard drives, not processors.

You should be able to share your data between hard drives without too much trouble. Depending on how they are set up it might be an idea to keep your programmes on C; though.