Some advice I found:
- See if this article helps : "How to Reset HP Pavilion Recovery CD One Limit Restriction".
- Found this on google : "find hpcd.sys, there will be 2 copies one in windows C:\WINDOWS\SMINST and other in E: rename hpcd.bak on both and you can make another set"
- Order the Recovery DVD from the HP website using product number in driver pages
- Try out the Restore Disks site.
Edit
If the recovery cd is now unlocked but burning it hangs, then most probably your recovery partition is dead (note: one dvd is not enough, so I hope it's not simply waiting for the 2nd one!).
From this article : HP Recovery Partition Low Disk Space (for XP), I understand that HP will update the recovery partition, and may destroy it if the allocated disk space for the partition is not enough to contain all Windows Updates.
If that's the case, then your only hope AFAIK is to get a new restore cd elsewhere than from your own machine, either from the above listed sources, or download one from Windows Vista Recovery Disc Download (I have no first-hand knowledge regarding this source, and you need bit-torrent software for it, but it's much referenced on google).