That should be possible by tweaking the code a bit.  In jombib.php lines 750 to 760 generate the authors name that is stored in the database.  If you change the order of this bit of code, you will get what you want.  However this change will only work if you re-add or edit your references.

if($sets['fullnames']=="on"){
  $authnames =$authnames.$author['first']." ";
  if($authorcount==1){
    $shortauthnames =$shortauthnames.$author['first']." ";
  }
}   
$authnames =$authnames.$author['last'];
  if($authorcount==1){
  $shortauthnames =$shortauthnames.$author['last'];
}

change to

$authnames =$authnames.$author['last'];
  if($authorcount==1){
  $shortauthnames =$shortauthnames.$author['last'];
}
if($sets['fullnames']=="on"){
  $authnames =$authnames.$author['first']." ";
  if($authorcount==1){
    $shortauthnames =$shortauthnames.$author['first']." ";
  }
}

Dear Pete,
I am not Mark, but I can give an answer to your secondo question:
In the file jombib.html.php
you can change the format how you like to print the title:
title without ":

if (HTML_jombib::keyExistsOrIsNotEmpty('title',$row)){
         if($link=="none"){
            echo ", ".$row['title']."";
         }else{
            echo ", <a href='$link' title='View Reference Details'>".$row['title']."</a>";
         }
      }

May be you can write the title also in italic:

if (HTML_jombib::keyExistsOrIsNotEmpty('title',$row)){
         if($link=="none"){
            echo ", <i>".$row['title']."</i>";
         }else{
            echo ", <a href='$link' title='View Reference Details'><i>".$row['title']."</i></a>";
         }
      }
The year with out ( ):

if (HTML_jombib::keyExistsOrIsNotEmpty('year',$row)){
         echo " ".$row['year']."";
      }

I did a copy from my site and I hope it works also on your site.
greetings
annette