Well, given the sample of data you've shown, this would do what you want (assuming the string is in $_):

s{.*<pre>}{}s;
[download]

That is, delete everything up to and including the "pre" tag. Note the "m" modifier at the end, so that "." is allowed to match "\n".

Now, if there's also a  </pre> tag that you're not showing us, and more html data after that, you'll probably want to get rid of that as well:

s{</pre>.*}{}s;
[download]

Of course, if a given html page contains more than one "pre" segment, you'll need to be more careful. Ultimately, you might need to actually read the manual page for an HTML parsing module, and start using it, because that would be the preferred approach for this sort of thing.

But if the data are consistently as simple as your sample, a couple regex substitutions will probably suffice.

(updated my regexes to use the "s" modifier as intendedm, rather than the "m" modifier. Thanks, mreece!!)