I am following the directions in the README at the CTAN entry for MinionPro. I am using the Minion Pro fonts from the Adobe Font Folio 11. I'm running a fully-updated TeX Live 2011 distribution on OS X Lion 10.7.2.
Please note that I'm entirely aware this can be solved by using XeLaTeX (with fontspec), but I wish to use LaTeX in this case.
Running otfinfo -v on any one of the 64 Minion Pro fonts yields,
Version 2.030;PS 2.000;hotconv 1.0.51;makeotf.lib2.0.18671
so naturally I'm using the enc-2.000.zip encoding files.
After unzipping metrics-base.zip, metrics-full.zip, metrics-opticals.zip, and enc-2.000.zip into my /usr/local/texlive/texmf-local directory, I ran sudo mktexlsr, then sudo updmap-sys --enable Map=MinionPro.map, then sudo mktexlsr again.
I then typeset my test file, whose code and output is shown below.
\documentclass[10pt]{article}
\usepackage[T1,T2A]{fontenc}
\usepackage[openg]{MinionPro}
\usepackage[utf8]{inputenc}
\usepackage[english,russian]{babel}
\begin{document}
\section*{English}
Hello! How are you? This sentence has \textbf{bold}, \textit{italic}, and \textbf{\textit{bold italic}} characters. This sentence has \textsc{small caps}.
\section*{Russian}
Здравствуйте! Как у вас дела? Это предложение имеет \textbf{жирные}, \textit{курсивные}, и \textbf{\textit{жирные курсивные}} буквы. Это предложение имеет \textsc{капительные буквы}.
\section*{Equations}
\[
\psi_{nlm}(r,\theta,\rho) = \sqrt{\bigg(\frac{2}{na_0}\bigg)^3 \frac{(n - l - 1)!}{2n[(n + l)!]^3}} e^{-\rho / 2} \rho^{l} L_{n - l -1}^{2l + 1}(\rho) \cdot Y_{l}^{m}(\theta, \phi)
\]
\[
y = x\tan(\theta) - \frac{g\sec^2(\theta)}{2v_0^2}x^2
\]
\end{document}

Note that the openg option also fails to display. This is strange to me, because it seems as if everything is working except for a few characters. Everything works great with XeLaTeX, but not when using the MinionPro package.
Forgive me if I'm being naïve. Thanks.

fontspec. I'm only perplexed as to why it won't work withpdflatex. – user2473 Jan 16 '12 at 22:40pdflatex, so it is a problem with your font setting. – Jan 16 '12 at 22:48