Microsoft Word (and similar applications) give you the option to set double line spacing, 1.5 line spacing and so on. LaTeX, on the other hand, is much more flexible.
The \linespread{spacing} command allows you to set any line spacing you like. For example, to get double line spacing, simply add:
\linespread{2}
to the top of the document. Simple.
I think what you have written is wrong. Use of \linespread increases spacing between text in tables, which is not generally desired. To obtain double line spacing, we need to use \linespread{1.6} instead of 2. A better way to have double line spacing is to use the setspace package and add \doublespacing in the preamble. Found it here. http://en.wikibooks.org/wiki/LaTeX/Customizing_LaTeX