\documentclass{beamer}
\usetheme{Hannover}
\begin{document}
\begin{frame}
\frametitle{A frame}
  \begin{columns}[T]
    \begin{column}{.5\textwidth}
     \begin{block}{Your textblock}
% Your text here
    \end{block}
    \end{column}
    \begin{column}{.5\textwidth}
    \begin{block}{Your image}
% Your image included here
    \includegraphics[<options, e.g. width=\textwidth>]{<your image file>}
    \end{block}
    \end{column}
  \end{columns}
\end{frame}
\end{document}