Victor, this is the sample file you wanted:

\documentclass[10pt,letterpaper,titlepage]{article}
\setlength{\pdfpagewidth}{8.5in}
\setlength{\pdfpageheight}{11in}
\usepackage[utf8]{inputenc}
\usepackage[spanish,english]{babel}
\usepackage[pdftex]{color,graphicx}

\author{Robert Marcano}
\title{Simple Image Sample}

\begin{document}

\maketitle

Simple test with images:

\includegraphics[scale=0.5]{bg}

\end{document}

the image file is named bg, do not add the extension, if you use pdflatex it will automatilcally search for an EPS, PDF, JPG or PNG file.