As of July 2010 no series 2009 or 2010 $2 bills have been printed.
Not sure about that. I know there was a large supply made in 2003 and there are some with a new slightly different design for 2010-2011 but i have yet to see one of the new redesigned ones.
Old US $1000 bills carried a portrait of President Grover Cleveland. Some privately-issued bills may have had a woman's portrait, though.
The Mint has never made $2 bills. The Mint strikes coins. The Bureau of Engraving and Printing makes bills, and it is a separate part of the Treasury Department. The first $2 bills at the national level were U.S. Notes issued in 1862. Private banks may have issued their own at an earlier date, however.
United States two dollar bills are common enough to supply everyone who wants them. Any bank may order as many as the customer wishes. The Bureau of Engraving and Printing will print more as they are demanded. There are currently over $1500000000 two dollar bills in circulation (as of 2010).
A person can exchange their old dollar bills at their local baking establishment. They may also exchange the bills for cash through a collector or dealer.
There were no US bills of any kind dated 1939. You may be thinking of 1934-series bills issued for use in Hawaii during WWII. Please see the Related Question for more.
The US has never printed bills with silver-colored seals. Bills called silver certificates were issued with blue seals, which may be what you're thinking of. Silver certificates were backed 1-for-1 with a dollar's worth of silver in the US Treasury. They were eliminated in the 1960s when the price of silver rose and it was no longer possible to back the bills with a fixed amount of metal.
The U.S. did not print any $50 bills with that date. You may have a note issued by a private bank, in which case you'd need to have it examined by a dealer or appraiser to identify it.
Please take another look at your bill and post a new, separate question. The first federally-issued $2 bills were printed in 1862. You may have a fantasy bill, something that was privately issued, or you may be looking at a date other than the printing date or series date.
You may want to consider going to a bank and exchanging the bills as "mutilated" for non mildewed bills.
There are no federally-issued $1 bills dated 1894. You may have a bill issued by a private bank under federal charter. If so, please post a new, separate question with the name of the bank and any other identifying wording or images.
Yes, both $2 bills and dollar coins are legal tender in the United States, so you can spend them just like any other form of currency. However, not all businesses may readily accept them, so you may need to check before trying to use them.