Yes, I too got that fishy smell when cooking with some veg oils. Then I switched to REAL butter. Ahhh, much better. I don't use margarine, ever. I often substitute Ghee. You could leave a jar of that out on the counter for a year with no trouble, remembering to put the lid on after use. India, the middle east, etc., use it exclusively. It's cows milk butter. Ideal for hot (or cold) countries with no refrig. I sometimes make my own, starting with real butter. Easy to do. Lots of "how to make it" info on the web.
As far as the medical professions "ban" on using real butter, for your health, that attitude is rapidly turning around, across the country (soon to come to a doctor near you). Our MD's at the hospital I practice at are starting to recommend it over all else. Atkins really set a fire under them.
DocVan
Oh, wait, I just noticed that all of the posters here at Granny's Kitchen, that I can identify, are women. As a guy who also loves to cook, have I accidently "gone where no man has gone before?" I'll quietly sneak away if I have.