If by "cash in" you mean convert to bills at face value, before I did that I would try to find out if anything in your collection is worth a premium. You'll need to look at a site such as http://www.coinclub.com/prices/ to get an idea. If there's anything made of silver, for example, it'll be worth several times its face value so you wouldn't want to get 100 cents on the dollar from a bank. If you're referring to selling the coins for their metal or numismatic value, I'll have to defer to the other experts who are familiar with the Atlanta area.
Old paper and coin currency can be sold to currency dealers. Old currency can also be sold online on the website, Ebay.
Numismatics is the study or collection of currency.
Old French coins would be called Francs. now the currency of money there is called Eros, but very old French coins were called Francs. Singular is Franc. Plural is Francs.
It will always be redeemable for face value at any bank, but taking old currency to a bank isn't generally a good idea. Depending on condition, it may have added numismatic value. Take it to a local coin shop for an appraisal. They will have books which rate and value currency.
Cash seems quite accepable eg can I pay by cash or by card? It is derived from the old word cache: a hoard of coin.
A Guinea is a coin of the old pre-decimal British currency. It was worth approximately 21 shillings.
The official exchange of Deutsche marks has come to an end. However, you can still take your old German currency to the Bundesbank (Germany's Central Bank) and exchange it for euros. Most currency exchanges (banks, airport exchanges, etc.) will only buy currency that is still in general circulation. Specialized currency exchanges such as Euro Coin Exchange (http://www.webuyeuros.com/germany) will buy your old marks, and you can get paid in dollars without having to ship your cash to Europe.
Some countries will do this when demonetizing their old currency and moving on to the new - and the N preceding a number is particularly seen with the Neuvo ("new") Pesos of both Uruguay and Mexico in the 1980s. (Thus, 5N would be 5 Neuvo Pesos). When a country does this, the citizens will be given a period of time to cash their money in for the new currency, and after that time has expired, their "old" money no longer has spending value.
One can find a coin price for old Argentinian pesos at your local Cash4Gold store. A dedicated agent will be happy to buy your coins in exchange for cash.
In the old British system of currency, a shilling was roughly equal to the American quarter, which is 25 cents.
Specially designed trucks and vans distributed decimal cash registers and cash / coinage across the country. Old Imperial money was changed into decimal currency as it was spent.
The old Papal currency was the SCUDO