It does depend where you go and it depends on your husband's job - hours/travel etc. It also depends upon whether you are likely to move to other countries or stay in the one you have chosen so that you can develop your career. This of course will be a completely different prospect in a developed country.
Nursing hours don't mix awfully well with children, a husband who might be travelling and no family around. Jobs like nursing and beauty therapy practical jobs - tend to be done in certain countries (Middle East/ Asia) by low paid locals or by immigrants from the Philippines or India.
Teaching has the advantage in that you will be employed on western style wages in British or International Schools , but it is true that the reputable schools will only really take you with at least 2 years experience. And you truly wouldn't want to work in some of the not-so-good schools. Tefl isn't usually regarded as a a career - more a part time job though you can earn well if you are good.
You can probably write if you don't depend on the money as there are often local expat magazines around. Tutoring English/writing might be a pastime. You might find work (in Asia or similar) writing and corecting English flyers for local businesses who want to attract expats to their product. Or helping with websites. In this kind of country women often set up small businesses to fill perceived gaps. eg: training maids in hygiene or cooking, holding writing groups or A Level/degree level study groups.
To be honest, 2 years will fly past as it takes most of a year to settle and it will be take a lot of your time helping children settle comfortably and make friends. If you've been happy with study and otherwise unstructured work until now, why will that change?
Go to www.expatexpert.com for advice from Robin Pascoe. She has written widely and sensibly on the life and problems of trailing spouses. There is also an trailing spouse's book by another author called "Career in your suitcase" to describe people in your position, written by a trailing spouse who wanted to have a career. (Don't believe her entirely when she claims to have succeeded - though it might be fair to say she has succeeded in achieving her own aims but there is bit of self promotion there).
Put bluntly, few trailing spouses manage a proper career if they have to move regularly. The exceptions are those who already have one before moving and even then it's hard. You can usually get a job of some kind though and even if you don't, you probably will, if you've the energy, manage to fill your time in a way you find productive, though without possibly making much money, if that's ok for you. Ask yourself if that's worked for you so far. The difficulties I describe are leading to companies having trouble finding good people for overseas postings because as more women (usually women) insist on their own careers, is is very hard to move dual career couples around.
The things that have worked for me have been online study and teaching (sorry - but if you are not keen don't train as it's hard work and expat parents in a good school are VERY demanding of your professional skills). For online study look at OU, Oxford University online short courses and browse other universities.
I have not regretted my peripatetic life at all, but I had reached a reasonable stage in my teaching career before setting out abroad and I wanted to stop and enjoy my children and have a change. I have done all those things and had fascinating times. I can't pretend to have had a career (though I have enjoyed the work have done) but my husband has had a wonderful one. You are very sensible though to imagine life at 50 without a career. It is a watershed for anyone when children leave, but extra tough if you are still moving round the world by that time because once the children have gone your life has no structure if you have no job and your friends are likely to be scattered round the world.
None of this applies if you're intending to go to somewhere like Australia and stay put for a good long time of course!