if its taking 30 mins to burn a dvd then its only burning at 2x not 8x.
what media are you using? post the brand and use dvdidentifier to get the mid.
what ide drivers are you using? if your not using the microsoft one`s then delete the ide channel reboot and windows will install the defalt drivers.
check your running in udma mode 2.
do a burst rate test using nero cd speed.