Whats the difference in them or is there??
Both fish oil and flax oil are Omega-3 fatty acids. Both are beneficial for good health. Fish oil provides DHA (Docosahexaenoic Acid) and EPA (Eicosopentaenoic Acid). Flax oil provides ALA (Alpha-Linolenic Acid).
Technically, the body can produce it's own DHA and EPA from ALA (And possibly from other fatty acids too. But not sure, do your own research on that one). The body has no ability to produce it's own ALA so you MUST get ALA from diet and/or supplementation. Theoretically this means that you only NEED to get ALA in your diet and you'll produce your own DHA/EPA. However, in reality, the body is not very efficient at producing DHA/EPA so you're better off getting ll three from diet and supplementation anyway.
If you want to be certain, take both, then all your bases are covered. that's what I do. I take Flameout, 5 gelcaps, EVERY day. I also freshly grind my own flax seeds and supplement with 2 tablespoons a day.
Whats ALA and what other foods have it?
There are many other threads that ask this question, try a quick search for them...
ALA (Alphalinolenic Acid) is an omega 3 fatty acid. Best sources for ALA are flax oil and I believe hemp oil. It's also contained in smaller amounts in dark leafy greens, purslane being one of the best leafy green sources, and walnuts.
Canola and soy oils contain ALA also, but I would avoid those sources for various reasons such as, the processing involved in producing canola oil can turn the essential fatty acids rancid, inflammatory, or hydrogenate them, essentially making canola a trans-fat. And we all know that processed soy products can be highly estrogenic.
Stick with Flax oil. Or better yet, get the whole seed, keep it refrigerated, and grind it fresh yourself before consuming. Keeping the seed whole and refrigerated will keep the fatty acids fresh and slower to go rancid. Make sure to grind it though otherwise the seeds will just pass straight through the digestive system. Ground flax will also add some fiber to your diet, and we can all use extra fiber.