$300-$400 build for non gaming PC w/ capacity for 3 monitors

I have decided to build a desktop PC for my home. This is my FIRST build and I'm not very knowledgeable on computer hardware. I will use it with the Microsoft Office Suite, stream/watch video and music, and to surf the web. Basically, I use a PC for random stuff and random software and not really for gaming. I am going to initially run it on 2 monitors and possibly a 3rd at some point later. I may add a blu-ray player and hook it up to a stereo receiver in my surround sound.

I am looking to spend $300-$400 right now not including mouse, keyboard, or monitors. What are your recommendations as far as :

- Case (atleast 2 external optical drives, usb ports)
- Power Source (should i get a case with one attached)
- CPU
- Video Card (do I have to get a certain type to run 3 monitors?)
- Motherboard
- Hard Drive/Storage (I dont download much music or movies so speed is > space for me)
- RAM
- Audio card (is it necessary to get for my purposes?)

Also, what (if any) special hardware/cards/processors do you need to make the PC play video through a TV with HDMI and high quality?

This is my first build and any input (specific or general ) you share is appreciated. Thanks!