The New Orleans Mint closed in 1909 so you can't have a 1926-O dollar. You may be seeing a "D" mint mark for Denver. If so, please check the Related Question for values.
The Morgan Silver Dollar can range from $25 to $70, and the Peace Silver Dollar from $50 to $300.
$27.
It's actually called a Peace dollar. Its value is around $14 to $16 for its silver content.
The first Peace dollars were struck in 1921.
Year: 1922D Mintage 15,063,000 Numismatic Value Range: $14 - $400$8.6870102468 is the total melt value for the 1921-1935 silver Peace dollar on January 16, 2009.ref:http://www.coinflation.com/coins/1921-1935-Silver-Peace-Dollar-Value.html
Each Peace dollar contains 0.77344 troy ounces of silver and is valued at $17.26 when silver is at $22.36 per ounce.
The last Peace dollar was issued in 1935 so it can't be a 1942 Peace dollar. Look at the coin again and post new question.
No US silver peace dollars were struck in 1929 or 1930.
There's a Peace dollar but not a war dollar. Please see the Related Question.
All Peace dollars are 90% silver. The current silver value is $15.28. The collectible value depends on the the date, mintmark and condition of the coin.
A 1924 Silver Dollar would include the Peace Dollar. If its mint state is very good (VG-8), the value is: $20. Should the mint state be MS-60, the value increases to: $35. A 1924 silver dollar is a Peace dollar, values for circulated coins are $17.00-$26.00. The term "Mint State" is used only for uncirculated coins.
A 1922 dollar with the word "Peace" on the back would be a Peace dollar rather than a Morgan dollar. "Morgan" refers to George T. Morgan, the artist who designed the silver dollars minted from 1878 to 1904 and in 1921. There's more information at the question "What is the value of a 1922 US silver dollar?"