I find long-acting, tablet ant-acids tend to work better than the short-acting chewable sort. Although, sometime liquid ant-acid (like liquid mylanta) can be great for very acute acidic-reflux.
I get chronic reflux due to permanent gastrointestinal damage, I take 40mg of Nexium(esomeprazole) and that generally keeps it at bay. My OTC/Supermarket antacid of choice is Zantac(ranitidine) - I try and keep this on hand for times when I haven't been able to get a new prescription (/ filled) in time when I run out/low on the Nexium, if I don't have it on hand and run into trouble, I can also buy Zantac straight from the supermarket - pharmacy not required, so very handy.