Which is better, Apache 2.0 or Apache 1.3?

Definitely 2.0. Except ... PHP depends on a lot of libraries. Not all of them have been verified as working properly with the new multi-threading of Apache 2.0. So you never know what might not be working right.

Now, I've got to learn PHP, but with 10 years of C and 8 years of C++, it shouldn't be too difficult, right?

Dude, you already know it, you just don't know that yet.

I bought the PHP Bible.

Lose the book. Go to [link|http://php.net|http://php.net] and follow the "documentation" link. All you need is the function list to start getting the syntax.