The second coin has a bifoliate crown by the looks of it (like two prongs on the out side of the crown).
The style is wrong for an Edward III (also they tend to have lots of annulets or saltaires in the legends), Given the style, I'd say Edward 1st, class 10. it's London mint.
With the 'foil and spit' - I use a similar method, but one that doesn't involve a lot of rubbing of the coin.
Get yourself some washing soda (it's about £1 for enough to last you years). Wrap the coin in some tin foil. Put it in a cup / glass - whatever you want to use to clean things! The put a reasonable amount of washing soda on the in the cup around the coin (in foil). Pour on boiling water. As it cleans your coin, it will smell - you can light the bubbles too, which is always fun.
Before the water has cooled completely, remove the coin and wash it - depending on the coin and how I feel, I either use an old cellulose sponge or an old toothbrush or my horsehair brush I got from a jewellers 25 years ago. This will clean most of the silver chloride off it, if it is silver.
If that hasn't completely done the job I then bung it in acid for a short while, but I wouldn't recommend this just yet