The first thing you need to do is check your magnesium intake.

If you do not take any, and do not eat nuts, oatmeal or beans, you could be very low.

You can test this with a soak in lukewarm (tepid)water and epsom salts. This can increase the circulation. If this works a bit for you, you then can take oral tablets, and apply a magnesium cream to open up the blood vessels. Sometimes this is from spasms only, and can be reversed. Do you take Calan, or Cardizem or Norvasc for blood pressure? These drugs can make that red foot thing worse.

If you have smoked cigarettes, you could have peripheral artery disease as well.

The turning colors and burning can be erythromelagia. This condition responds to magnesium therapy.
Dr. Jay Cohen MD had this himself, and writes about it on his website:
http://www.medicationsense.com/erythromelalgia.html

Spasms come and go.... blocked arteries don't change. So if you have times with less issues, then more burning, consider Dr. Cohen's advice.
He has written a book on Magnesium, which discusses it.
http://search.barnesandnoble.com/Mag...I=Jay+Cohen+MD

Here is an excerpt:
http://books.google.com/books?id=oD3...trophy&f=false