The first thing to do when faced with mortgage arrears, and this is really serious advice: Don't Panic! I'm not quoting Douglas Adams for the sake of it, I really mean "don't panic". If you do panic, you won't think straight and this is when mistakes can and will happen.
I first had mortgage arrears in the early nineties when there was a real property crash. I simply could not afford my mortgage payments and it got so bad at one point that I was actually nine months behind in my payments. But, before I go on, I need to explain that I not only avoided repossession but also paid off that mortgage in full not too long after those desperate days.
The most important thing you can do is keep in touch with your lender. They feel much more secure when they know you are not avoiding the problem and will often be very adaptable to your circumstances.
When the rising interest rates becomes a real problem is when the outgoings outgrow your incomings - especially if you have a lot of other debts like credit cards and unsecured loans. This is when the option of selling your house and renting it back becomes a potential idea. The only thing to watch out for (and this is important) is to make sure that the company that offers this gives you a tenancy agreement for a period of time that you agree to, as well as a buy back option in the future so you can get to keep your house when things turn out better for you.