Was told to re-install 12.04 to access other disc on my Toshiba Satellite. Got 12.04 download onto a CD as instructed - took hours and hours to download and was useless.

Upgrades asks for this CD when told to install upgrades and fails when the CD is installed. Not inserting the CD has the same effect. I now have over 300 upgrades waiting! How do I get past this?