IMO, my good friend signals is correct as always...

I think this might be an...all too typical...crappy, hp firmware, support issue.
With any luck, this could be a liteon burner with horrible hp firmware

Are you by chance using -R blank media?
Please try verbatim DVD+R media, the regular SL discs (dvd5, 4.7 MB, which are really 4.38 MB btw). You can get 'em anywhere...bestbuy, circuit city, office max, etc., etc.
You should bitset to DVD-ROM, but we can get to that in a minute.

Download and install nero cd-dvd speed...link in my sig
It's a free and very useful utlility and will give us much of the info we need to help you.
Put one of your blank discs in your burner, open nero cd-dvd speed, click
Disc Info.
This will display your burner, make, model, firmware and the blank media code (MID). In this example, one of the verb blanks I mentioned is displayed.
Post the attachment as below.

There are a variety of ways to bitset, both automatically...(depending upon the specific burner) and manually.
For now, simply click Extra in nero > Bitsetting.
See below.

You also may consider flashing your firmware (once your burner is ID'd) to something more useful. A word of caution however, this will void any manufacturer's warranty.