Hello,
Change your document to something like
*******************
\documentclass{memoir}
% \usepackage{ucs} %needed only for LaTeX
% \usepackage[utf8x]{inputenc}
\usepackage{xltxtra}
\begin{document}
\setmainfont[Mapping=tex-text]{Minion Pro} %<--- Choose any font you like
101 × 101
\end{document}
*******************
A.S.
----------------------
Apostolos Syropoulos
Xanthi, Greece
--------------------------------------------------
Subscriptions, Archive, and List information, etc.:
http://tug.org/mailman/listinfo/xetex
