Yo-

Use your original acronis true image cd to boot up and start your computer with the acronis program - select drive to back up - and point it to your available DVD drive - in options select the 4300 size - have a bunch of good (verbatim or tayio yuden) dvd discs available and start your backup - following the instructions when it tells you to put in a new disc.

A much easier and far more reliable way - is to use an external hard drive to backup on to - I personally use a 250gb external Fantom hard drive that costs around $70-eh