We have loads of Almonds which have developed a strange back taste(maybe rancid) they are eatable but the flavor has changed probably due to extended storage , so we decided to extract oil out of it but is it good to use such almonds for oil? What are some other uses of such almonds? 
If they truly are rancid, then you should just discard them.  Any use of the almonds or their oil will just impart a terrible taste into the dish in which they are used.  If they have gone sour (I am not sure how that would be possible), then something is very wrong, perhaps an unusual type of spoilage, and similarly you should just discard them for safety reasons.  Either way, unfortunately, I don't think you should use them. 