lethargic_man | Web authoring advice

I've been sort-of commissioned to make a website for Marom. Now the only complex websites I've made until now have been strictly functional ones for work, driven by Perl CGI backends and with no security measures, as behind work's firewall. I can stumble my way through simple JavaScript from knowledge of C++, but don't know any Flash.

So I have a few questions for anyone who's made a public-facing website beforehand:

Firstly, any recommendations for an host ISP? This is a site of interest probably only to a few hundred people, but those few hundred might be visiting it frequently.

Secondly, as regards making it updatable by non-techies, I was thinking of providing proformas and inclusion of "what's on this week" files, etc, by server-side includes. Are server-side includes something ISPs are likely to provide?

Thirdly, would I stand a chance of having Perl available as a backend? And if so, how do you make it secure? I gather taint-checking is involved; once I've taken that into account, can I leave it all to Perl? Actually, I probably don't need Perl for the basic proposition, but when I was talking about it with Assael, he waxed lyrical about the possibilities -- message boards, a dating subsite, the works -- and it would be nice to be able to extend the site after its initial launch.

Any other advice whilst I'm at it?