Well, okay. First things first.
echo("Text");
echos "Text" to the browser, I assume you understand that.
echo("<? pv($prod->image) ?>");
echos "<? pv($prod->image) ?>" to the browser. This means that the above text is actually sent to the browser, and NOT parsed by PHP (wich is a server-side language, remember?)
So, what you need to make this work, is loose the quotes, so it's treated as a function (wich it is), and not as text;
echo(pv($prod->image));
Now, if you want to echo a quote ('"') to the browser, you'd do the following;
echo("\"");
Put a slash in front of the quote to escape it, so PHP knows that this is not the end of a string. You escape the 'i' in 'images', not the quote.
To combine a string with output from a function, use '.' to concatenate it, i.e.:
echo("this is a string containing function output: " . some_function() . ", wich is nice.");
What you want to do is most likely;
echo("<class=label><br>Image</br>
<class=normal><img src=\"images/cart/products/".pv($prod->image).".jpg\"><p></p>");
Or something like that.. 🙂 In a hurry, hope I didn't miss anything important 😛