Windows 7: severe problem,need urgent help!!!

hi...
i always got this problem since i bought dell studio 1737.and i searched on web,and noticed that this is more common with dell laptops...
i have windows 7 ultimate x64 and when i try to burn windows 7 image on dvd using ultra iso to make a bootable disk,it says DVD R/RW requires settings to use DAO mode,i contacted dell and got to know that my DVD writer is in PIO mode and must be changed to DAO or DMA....i dun know which is right,ultra iso says,DAO mode andweb search says,DMA mode...

1..i contacted dell and they gave a little utility to install,i did...but it didnt work and my drive is still in PIO mode.
2..then i searched web and they told me that i go in device manager and uninstall driver for primary and secondary IDE drives and reboot and it shall go to DMA mode itself,but i dun see primary and secondary IDE in device manager (i have attached pix)
url: (DMA reverts to PIO | Windows Problem Solver) and (Enable DMA mode in Windows XP)
3..i got some registry solution on web too,but again same,they say to delete MasterIdDataChecksum
SlaveIdDataChecksum but i dun find in my regedit path (HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\
Class\{4D36E96A-E325-11CE-BFC1-08002BE10318}\000x)
pic attached



url (Getting back to DMA mode in WindowsXP | Sniptools | Miscellaneous)

now tell me what i do....

Rather than going to the drives in the Device Manager, see if you have an item listed under IDE/ATA ATAPI Controllers titled ATA Channel 0 or 1. If so, open each of their properties and select the Advanced Settings Tab. At the bottom of it there should be a checkbox to enable DMA.

this option i showed in pix,to enable DMA is already clicked and on..but drive is in PIO mode....

Welcome to Windows 7 support forums,
Awai, may I suggest you access the bios of your system and check your storage setting and see what the deaults are? Basic I/O dictates if you will be able to access Ultra/DMA Consult your specs and identify whether your drives are SATA/AHCI type connections.

Regards,
Adrian

well as u said,i checked in BIOS,as u know in laptops,there isnt much details,but anyhow,i found SATA mode controller was on AHCI and other option that could be changed with was IDE...
i have no idea wether it will solve the problem or not,or will make a new problem.at present my laptop has 2 hdd, 320gb as primary n 500gb as secondary...
so what u suggest in this condition....