Color page inside of the set height and width

I'm not sure what exactly you want. You can use \rule together with \textcolor to get a colored rectangle:

\documentclass{article}

\usepackage{xcolor}
\usepackage{lipsum}

\begin{document}
\lipsum

\textcolor{green}{\rule{10cm}{9cm}}

\lipsum
\end{document}

If you want some colored block drawn in the background you can do this using TikZ, when you use the options remember picture,overlay in the page header, or direct after \newpage. If you want to draw the colored box to the text area margins use my recent tikzpagenodes package:

\documentclass{article}
\usepackage{tikzpagenodes}
\usepackage{lipsum}

\newcommand*{\newcoloredpage}[1]{%
    \newpage
    \begin{tikzpicture}[overlay,remember picture]%
        \fill [#1] (current page text area.south west) rectangle (current page text area.north east);
    \end{tikzpicture}%
    \vspace{-2.5\baselineskip}%
    \par
}

\begin{document}
\lipsum

\newcoloredpage{blue}
\section*{Review}
\lipsum[1]

\newpage

\lipsum

\end{document}

If you want to color the background of a paragraph you could use adjustbox with the minipage and bgcolor keys (and maybe margin to add some more margin):

\documentclass{article}

\usepackage{xcolor}
\usepackage{adjustbox}
\usepackage{lipsum}

\begin{document}
\lipsum

\begin{adjustbox}{minipage=\textwidth,bgcolor=blue}
\lipsum[1]
\end{adjustbox}

\lipsum
\end{document}

However, such a paragraph can't be broken across the page. If you need this the framed or better the more modern mdframed package would be the way to go.
_{I'm working on a TikZ-based decoration package which would be usable here as well, but isn't finished yet.}

can be done with a tabularx:

\documentclass[10pt,a4paper]{article}
\usepackage[table,dvipsnames]{xcolor}
\usepackage{lipsum}
\usepackage{tabularx,xhfill}

\begin{document}

\noindent
\begin{tabularx}{\linewidth}{ X !{\color{white}\vrule width 2pt} X }
\rowcolor{SkyBlue}
\multicolumn{2}{>{\columncolor{SkyBlue}}p{\dimexpr\linewidth-2\tabcolsep\relax}}{%
  \leavevmode\rule[-2ex]{0pt}{6ex}\Large\xrfill{2pt}[white]\sffamily\ 
  Review
  \xrfill{2pt}[white]}\\
%
\rowcolor{SkyBlue}
\lipsum[1] 
&
\lipsum[1]
\end{tabularx}

\end{document}