A couple of quick comments (more later on tonight if I have time and remember, but feel free to PM and I'll reply by tomorrow night):
(1) FileVault is evil incarnate. Well, not literally, but if
anything gets corrupted, your whole home directory is gone. Forever. Period. FV puts everything into one big encrypted file, and it's very risky. Not only that, but I don't think it provides much if any protection if you're logged in (could be wrong). it is
much better to create encrypted disk images for sensitive files (Applications->Utilities->Disk Utility, ask if you need help).
(2) It's somewhat easy to change ports on Apache. Very easy once you've done it before. I personally would recommend going to
Apache and downloading and installing Apache 2.2.0. The instructions there are pretty good, but ask if you have problems. You'll then have built and installed your own version of Apache, which will fill your soul with geek mojo. You'll then feel more empowered to screw with it. And... there is a
lot you can do. Change or add ports to listen on. Add support for SSL. Link to external folders. All kinds of stuff.
(3) If you set up Apache to listen on a port other than 80, odds are you'll be a lot safer from hacks because most script kiddies go for port 80. Also, Apache HHTP Server is reasonable secure anyway, and it's pretty simple to lock it down. I don't think you need a virtual machine, although of course it wouldn't hurt - but it'd suck away CPU and RAM.