My C220 Classic won't start
 

Hi i have 2003 C220 classic auto and have a slight problem with it it won't start at all it will not even turn i was wondering if any body had any ideas as to what the problem may be or may have had the same problem. heres what happened i was driving my car doing a few messages i stoped at a shop and when i came out the car just wouldnt go i was left stranded miles from home. a mechanic i know thinks that it could be the ignition switch any ideas please if this helps a couple of times when i was getting out of the car i could not get the key out of the ignition it was almost as if it was stuck.

any ideas or solutions welcome