This is most likely caused by Sonic DLA. Remove that program and see if the error goes away.
If that does not help, please see this thread from the Dell forums where I was helping someone with the same problem:
http://en.community.dell.com/forums/t/19281563.aspx
I recommended several ideas but never found out if the problem was solved.
DELL DIMENSION 4700 WINDOWS XP HOME SERVICE PACK 3
NEC DVD+RW ND-2100AD
When I insert a DVD into the drive I go straight to the blue screen of death, reading:
"BAD_POOL_HEADER
*** STOP:0x00000019
(0x00000020, Ox87F9F710, 0x87F9F728, Ox1A030001)"
I have tried re-installing the DVD driver but this makes no difference. This is the first time I have had the problem since installing service pack 3.
Any ideas?

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic