I'm with Ian on this one. Reading books is all well and good, but nothing beats getting stuck in. I actually started with a Dummies Guide to ASP (that'd be "classic" ASP), back in 1999.
If I was going to start from scratch today I'd be looking at something that covered a full stack solution, whether Apache/PHP/MySQL, RoR or whatever.
ATM I have no experience of Rails, but it might be a pretty good place to start as it includes a lot of stuff that you'd have to figure out early on otherwise (integration with a Scriptaculous, a JS framework) - you can always learn what going on under the hood at a later date.
.NET is always an option, and if you're comfortable with Visual Studio it may be the way to go, but it's not the easiest thing to pick up otherwise.
If you know a bit of HTML but are basically new to server-side programming you might look at ColdFusion. It's actually extremely powerful and like Rails includes lots of "out of the box" benefits. There's a Swiss company called Railo who are currently in the process of releasing an Open Source ColdFusion engine that is affiliated with JBoss.
Last and not least - don't forget databases! Sooner or later you'll need to get to grips with some pretty serious SQL...