Looking for advice on home file server

Hello all,
Currently I have a HTPC with two drives in it (1TB & 1.5TB). Realizing that I have no redundancy right now, I was thinking of building a new system to function solely as a media, utorrent, & squeezebox server. This system would need at least 3TB of storage (more would be preferable), but I didn't want to spend more than $500-600. Here is the system I spec'd out on Newegg.

Antec 300 case w/ 380w 80+ psu
Foxconn G45M-S mobo
Intel E7400 cpu
2 Samsung Ecogreen2 1.5TB drives
2gb ddr2 800 ram

This setup comes in at around $500. I was planning on taking the 1.5TB drive I currently have and adding it to the 2 I'd buy to create a raid 5 array, giving me the 3TB I want. However, I know that software raid 5 is rather slow, so I'm not sure how much of a negative impact this will have on me serving media, since it's mostly reads (the only writing will be torrent traffic which is limited by my fios connection at 25mbps). Do you think raid 5 would be a bad choice for this setup? Would spending $300 extra on a hardware raid card be worth it for this type of system? Or should I just say screw it and do a raid 10 and spend an extra $100 for another 1.5TB drive.

I know there's a lot of scenarios, but I have so much running through my mind and could use a voice of reason to clear everything up for me...

PS... I'd like to keep this as low power as possible without sacrificing performance (no overclocking or core 2 quads)

Well, I went ahead and purchased the above system. I didn't want a JBOD setup because data redundancy is a must. Also, power consumption is a concern, but isn't my highest priority. I didn't feel it was worth trading Intel's superior performance for the extra power savings that AMD offers.

Now that I have the new system, though, I'm debating on whether to configure the array for RAID 10 or 5... It'd be nice to have 4.5TB storage, but at the same time, I'm not sure how well ICH10R handles writes in RAID 5. What do you think is better, 3TB in RAID 10 or 4.5TB in RAID 5. I currently am using about 1.7TB just to get an idea.

That article is what made me think more heavily about RAID 5 actually. But then I realized that those results were with SSDs... if a degraded SSD array writes at 30MBps, I don't even wanna know how an array of regular hard drives will fare