I must answer this!
For the second part, you could clip your pictures.
The "pizza" images used in the \includegraphics
of my MWE are from the cook duck of the duck pond with different backgrounds, of course, you'll have to change them into your own images.
\documentclass{article}
\usepackage{tikz}
\usepackage{subcaption}
\tikzset{%
mynode/.style={draw, circle, very thick, inner sep=1.5pt},
myseparator/.style={white, line width=1mm},
}
\begin{document}
\begin{figure}
\centering
\begin{tikzpicture}
\begin{scope}
\clip (0,0) -- (3,0) arc (0:75:3cm) -- cycle;
\node{\includegraphics[width=.5\linewidth]{pizzacyan}};
\end{scope}
\begin{scope}
\clip (0,0) -- ([shift={(75:3cm)}]0,0) arc (75:170:3cm) -- cycle;
\node{\includegraphics[width=.5\linewidth]{pizzared}};
\end{scope}
\begin{scope}
\clip (0,0) -- ([shift={(170:3cm)}]0,0) arc (170:210:3cm) -- cycle;
\node{\includegraphics[width=.5\linewidth]{pizzagreen}};
\end{scope}
\begin{scope}
\clip (0,0) -- ([shift={(210:3cm)}]0,0) arc (210:360:3cm) -- cycle;
\node{\includegraphics[width=.5\linewidth]{pizzablue}};
\end{scope}
\draw[myseparator] (0,0) -- (4,0);
\foreach \myangle in {75,170,210} {%
\draw[myseparator] (0,0) -- ([shift={(\myangle:4cm)}]0,0);
}
\foreach \myangle/\myname in
{40/cyanslice,130/redslice,190/greenslice,290/blueslice} {%
\node[mynode] at ([shift={(\myangle:2cm)}]0,0) (\myname) {};
}
\draw (cyanslice) -- ++(1.4,0) -- ++(.5,.5) node[yshift=.4cm,
text width=7em, anchor= north west] {{\LARGE 20\% }\\Prosciutto\\ e funghi};
\draw (redslice) -- ++(-2,0) -- ++(-1,.5) node[yshift=.4cm,
text width=6em, anchor= north east, align=flush right] {{\LARGE 30\% }\\Margherita};
\draw (greenslice) -- ++(-1.4,0) -- ++(-.5,-.5) node[yshift=.4cm,
text width=7em, anchor= north east, align=flush right] {{\LARGE Car\LaTeX}\\Salsiccia e \\ friarielli};
\draw (blueslice) -- ++(2,0) -- ++(.5,-.5) node[yshift=.4cm,
text width=5em, anchor= north west] {{\LARGE 40\% }\\Napoletana};
\end{tikzpicture}
\caption*{Preferred pizzas by Italians\\ (no pineapple one on the rankings)}
\end{figure}
\end{document}

P.S. = The percentages are random.