colored table with some bold colored lines

Question

How can I have a table with the following specifications:

1. The top and bottom lines are bold and all other horizontal and vertical lines are normal.
2. The whole table lines (including top and bottom lines) are in red color.
3. The whole table have an yellow background.

Answer 1

\documentclass{article}

\usepackage{colortbl}

\arrayrulecolor{red}
\def\widehline{%
\noalign{\global\dimen1 \arrayrulewidth
\global\arrayrulewidth8\arrayrulewidth}%
\hline
\noalign{\global\arrayrulewidth\dimen1 }}

\begin{document}

\colorbox{yellow}{%
\begin{tabular}{|l|l|}
\widehline
1&2\\
\hline
aa&bb\\
aaa&bbb\\
\hline
3&4\\
\widehline
\end{tabular}}

\end{document}

Answer 2

Here's a possibility using the tabu package:

\documentclass{article}
\usepackage{tabu}
\usepackage[table]{xcolor}

\begin{document}

\noindent\begin{tabu}{| l | l | l |}
\taburowcolors1{yellow!90!black..yellow!90!black} 
\taburulecolor{red}
\tabucline[1pt]- 
column1a & column2a & column3a \\
\tabucline- 
column1b & column2b & column3b \\
\tabucline- 
column1c & column2c & column3c \\
\tabucline- 
column1d & column2d & column3d \\
\tabucline[1pt]- 
\end{tabu}

\end{document}

As a personal suggestion, vertical rules are not necessary and your table will look better without them.