Hi I'm a doctor and I've personally taken anti-malarial medications (doxycycline). I'm pretty sure you should take them if you're going to India, but not every malaria-prone country is 100% malaria prone- it depends on which area you're travelling to. If you want to be sure, go to
Destinations - Fit For Travel. We use this website a lot when advising people whether they need prophylaxis.
Doxycycline is cheap and very straightforward- just a tablet a day. It does, however, in certain people (and I was one of them!) produce a horrible, red, blotchy, itchy sun-sensitive rash on your face. Given that it's India, it's pretty hard to avoid sun. Yes, the rash comes up even if you've slapped on layers on sunscreen. It varies in individual people, though- some are lucky. The other side effect is heartburn/indigestion. To avoid it, you should take it while sitting up and avoid lying down afterwards- but even so, my travelling companion still got heartburn from doxy
The other option is Malarone. I've never taken this, but it's also once a day. it's more expensive but you don't need to start as early. It also has much fewer side effects, according to some people.
But you should really speak to your doctor, because there are quite a few other vaccinations etc. that you may need eg. hepatitis A, typhoid, and probably cholera. The cholera vaccine (a fizzy drink) is pretty awesome- it also protects you against traveller's diarrhea and food poisoning of most sorts. It was the best investment I've ever made before going to SE Asia... I ate all sorts of random stuff off the street without getting sick once!