I have several old coins from 1881 Indian Head Cents to 1902 Barber coins. I also have a coin (I think it is a dime) with a big "V" and a wreath on the back It is dated 1900. What is this coin?

I wouldn't clean them, I think you have a "V" Nickle:
The Value of V Nickels - From Common to Rare (http://www.coinstudy.com/value-of-v-nickels.html)