IPOD dock in glove box is pretty crap, basically use it to charge the IPOD. As far as playing stuff - forget it. You can create 5 playlists on your IPOD then play "find the play lists" on your head unit.
To play the IPOD through the system you press the CD button once to play CD's, twice to play tracks off IPOD, and three times to access the AUX function, fourth press returns to CD. Problem is when you get to IPOD function you cannot see track names (or any information at all except "Track xxx"
You can use the streering wheel controls to skip forward-back etc.. but you don't know whats playing until you hear it.
As a stand alone option for around £200 its about as useless as they come. I've only got it because it came with the sound pack (6 x CD) and as "ADAM" says you're much better off burning MP3 discs to play in the unit.