Gary wrote:
How can I delete read or unwanted subjects from this newsgroup?

You can't actually delete them, but some newsreaders can be set to
"ignore" threads.

In Thunderbird, simply pressing the "k" on the keyboard does it. In
X-news I think it's the delete key. (In X-news, "k" is for plonk.)

But you seem to be posting through google, so you probably just have to
suffer through them.