HD-XA1's door won't open

Dear Sir/Madam,
Today I powered up my HD-XA1 for the 1st time and the word 'setup' appeared on the display.Without referring to the separate leaflet with tells you to go to certain pages of the manual before you start using it in a regular way, I inserted a HD DVD disc(The Mummy) and now the player displays the word 'welcome' but won't respond to any command,either with controls on the unit or the remote.The disc is stuck inside.Is there a way you can reboot the unit like they way you would a computer(ctrl,alt,delete)?You can't even switch off the unit with power button on the front.
Please help.THANKS