\documentclass{article}

\usepackage[pdftex]{graphicx}

\begin{document}

{\bf {\Large Figures in Latex}}

\includegraphics{"c:/Users/Bisan Co/Desktop/classes/Spring_09/Latex/Test_Files/figure"}
%\includegraphics{figure}

\includegraphics[height=4in]{"c:/Users/Bisan Co/Desktop/classes/Spring_09/Latex/Test_Files/abc"}

\begin{figure}
  \begin{center}
    \includegraphics[width=3.5in]{"c:/Users/Bisan Co/Desktop/classes/Spring_09/Latex/Test_Files/figure"}
  \end{center}

  \caption{\small This is ...}
  \label{fig1}
\end{figure}

\end{document}