I have an Acer Aspire. i have an Acer Aspire M1640 (Desktop) came with windows vista homeprenium

Question

i have an Acer Aspire M1640 (Desktop) came with windows vista homeprenium but i want to install xp on to it .. but when i do and try to burn a dvd or cd with NTI or NERO the cd always fails saying the desk is full .. but they are brand new disks and work in my other PCs and the dvd burner works great in vista but the problems crop up when i am using windows xp