* In your initial post you were looking to increase the burning speed of your external DVD+/-RW drive, but in your most recent post you are looking to increase the speed at which your internal drive reads DVDs. Which one are you looking to accomplish, or is it both?
* I looked up your computer's specs and found that your internal DVD-ROM drive can read DVDs at 8x. Are you sure it's running at 4x?
* What speed media are you using? Each DVD is rated at a different speed, so if you have a DVD player capable of 16x and a DVD limited to 4x, you are only going to be able to play it at 4x. The only way around this would be to purchase DVDs that support 16x speeds.
* If your DVD-ROM only reads DVDs at 8x, you're pretty much stuck at 8x unless the manufacturer has released a firmware (not driver) update that increases the maximum speed supported by the drive. The same goes for your DVD burner.
* For any guidance dealing with your internal DVD-ROM drive and external DVD+/-RW, we need to know the exact model number of the drives. You can look on the outside of your external drive, but for the internal drive you'll need to download and install a free program such as Everest. Look under optical drives and write down the model number.
* Updating your firmware can be risky, and if done improperly it could render your drive unusable. Thus, I'd suggest just continuing at it's current speed, or purchasing a new, faster drive.
Hope this helps,
P.S. Like Grif mentioned, please use punctuation...it makes posts much easier to read and understand.