Need help building a new computer

Hey guys, I haven't been here in a looooong while.... med school is eating up my life.

It looks like my desktop finally died... I want to replace it, but I've got no idea what's what in the computer world anymore. I would just make my life simple and get a laptop, but I just bought a 24 inch LCD a few months ago, so I'd like to continue to use it. I'm not looking to do any gaming on my system - I haven't got any time for that. At most, I might get Spore and muck around with it here and there. Or something like Civilization now and then. Really though, I doubt I'll be playing much, if any games.

Basically what I'm looking for is a system that is strong enough to play back 1080p without stuttering, and will be Blu-Ray compatible should I ever choose to get a blu-ray drive. I think my HDDs still work, so I shouldn't need to get any more, but I think I need to replace the rest (case included?).

Could I get some advice on systems that will suit my pretty basic needs? I use my pc for watching movies, listening to music, web browsing and Microsoft Office style apps. I really don't need anything special, but like I said, I know nothing about the current world of computer parts and I don't want to go into the local computer shop and have the dude there try to rip me off.

Again, I need: a motherboard, an Intel CPU (Core 2 Duo is the lowest I want to go), memory, a graphics card (my Radeon 9800 PRO is a little old now...) and... a case/power supply.

After some quick browsing I was thinking of the following:

CPU: Intel Core 2 Duo E8400 Dual 3.00GHz 6.0MB 1333FSB S775
mobo: ????
case/PS: Antec Sonata III 500 or Sonata Designer 500
memory: ??? I'd probably want 4 GB
graphics card: ???
optical drive: already have one
HDDs: have 2x SATA drives

Jam it back in, in the dark.

Ya, I won't be doing much gaming aside from MAYBE randomly playing Spore or Civ every now and then. Those aren't super high end graphics games, so I don't think I'll need a top of the line card to run them.

My budget is probably 600-800$ (Canadian). I'd be shopping at either MicroBytes Montreal Computer Ordinateur or Informatique Sigmawave Inc. . They have more or less the best prices I can get in Montreal, and they'd be able to set up the Mobo for me (since I have no idea how to do it and don't really feel like wasting time figuring it out). I don't really want to spend a lot, but I want something of decent quality that will last me a few years.

I don't even know if I actually need a new case or not. I currently have an Antec Sonata - but I don't know if computer parts have changed sizes since I bought this machine in 2004.

There's nowhere I can't reach.