Hi Richard,
Welcome to the group!
The "List" referred to is Java's "java.util.List" class: you'll need
that in the import statements at the top of your java code. We also
use generics, so you'll need to be using Java 5 or above for this to
compile.
You may find that the "Select" class in the webdriver-support.jar is
useful to you. From your example, it could be used like this:
WebElement element = driver.findElement(By.tagName("select"));
Select select = new Select(element);
select.selectByVisibleText("want this");
The fully qualified name you'll need in the import statement is
"org.openqa.selenium.support.ui.Select".
Regards,
Simon