If I were to manually delete all the Host and PTR records for the PC's on my network are they going to automatically be recreated the next time a computer starts up and queries DHCP for it's IP address.
My DNS seems to have got a bit random. I have a number of duplicate addresses in both the forward and reverse lookup's. An interesting example is the entry I just deleted. PTR Record for "English2" IP 172.16.1.12 has just recreaeted itself. "Associated A record I hear you cry" (possibly). Well there is currently no record for English2 in the A records (I delete them earlier just to see what happens when the machines get switched on to experiment to find the answer to the above question) and the reserved IP address for English2 is 172.16.1.11.
I've never had any issues with manually deleting all the DNS records, I've had to do it a few times at various locations.
As you say they will be automatically re-created next time the PC is started up.
If you have multiple DNS servers, then don't forget to delete the records on all of them.
As always, be sure to check your scavenging settings. I posted about how to check this here:
Deleting the records should do no harm, as long as you don't delete a server's entry by accident. It happens. :o