ACR Color Shift

If ACR and Photoshop don't match, the monitor profile is either defective or corrupt, or the wrong profile is used in a dual display setup.

The latter is less common, but sounds like it might be the case here (since ACR main and ACR filter are different). This has been reported in some cases lately, mostly under Mac OS in a laptop <> external display configuration.

Try to swap the main/secondary displays, just as a test. Whether this is an OS issue or a PS/ACR issue I don't know. I don't think it was ever resolved. It doesn't happen to everybody, which I suppose is the definition of a bug.

The profile you choose in ACR will be the profile embedded with the image when saved to a file or opened in Photoshop. Photoshop will honor that profile by default and the colors should look correct.

It sounds like you are trying to say that the colors look different in ACR and Photoshop?

Reset your Photoshop color settings back to e.g. one of the general purpose defaults if you have been messing with them without really knowing what you are doing!

The default RGB working space in Photoshop does not override the profile of the image file; so it is fine to leave it at sRGB (typically what you want) even if you are opening ProPhoto or AdobeRGB images. Never change the "Advanced controls". Here is an example of what decent color settings may look like: http://imgur.com/NKCl9BV

If the colors still shift between ACR and PS, then check your video card that you haven't enabled any color adjustment there (if using nvidia/ati under windows) and see if enabling/disabling GPU acceleration makes a difference perhaps? And reset your preferences as well in case they have somehow gone bad.

Ps: Prophoto is huge compared to what colors your original photo likely contains, and huge compared to what your monitor is physically capable of displaying. It is fine as long as you work in 16-bit, but I would generally recommend working in a more reasonably sized color space (e.g. AdobeRGB) unless you have some very specific needs.