The short sale option may be a good one, but you generally need to be behind on payments to qualify, and as Michael mentioned, your credit will be severely impacted for years. That impact will hurt more than just your next home purchase, but any credit application and often interest rates on revolving debts.
Have you looked at a HARP refinance? This is only useful if you keep the house, but you could possibly rent the home for a while to pay down the mortgage. Just keep in mind with being a landlord, you might have big expenses still, like a roof or A/C repair. You may already have good interest rates since you recently refinanced, so HARP may not work for your situation, but worth a look.
Doing a sale by owner isn't always a good financial decision. Often, you can obtain more for your house selling with an agent than by owner, and it often exceeds the cost of the commissions. Also, if you're in Newtown now and your house is in Georgia (assuming from your location setting), you would have to rely on relatives/friends to show the home. Furthermore, if you did a short sale, then the lender would require a Realtor to list the house, but the lender usually pays the fees.
In generally, I would recommend against a short sale. It sounds like you need to talk through your situation with at least a local Realtor, and possibly a mortgage lender to get personalized advice.