The PC looks good for the job.
I would still be looking to take the load of DAC/ADC duties away from the "onboard" hardware.
It can get glitchy trying to run graphics (waveforms), a full DAW, or any VST plugins/effects and such, so I typically take the load off the supplied onboard soundcard with an external USB one.
There's nothing worse than glitches in your recording as your HDD seeks in one spot for playback and seeks in another spot for recording, then another for a background process in Windows, so the 2 X HDD setup is a good idea.
Most professionals I know use at least 2 HDDs, it offers better workflow. YMMV.
You can get a cheap DAW, called "Reaper", with a trial version and I think, licence for $60 (was last time I checked):
http://www.reaper.fm/
Even coming from a professional studio environment, I found Reaper to be overwhelmingly complicated for what is a relatively simple task, but open source can be a bit like this.
Other introductory type DAWs like Magix may be cheap and cheerful for a MIDI user.
I've not used MIDI in 20 years, I play live instruments, so my advice is limited on the interface side of things.
That Focusrite looks good for the money.
Personally, I would steer well clear of torrenting a DAW, or otherwise...
Most have security keys, and protections in place that (unless you're an expert user) can make life very difficult, should one choose to download one from an unknown source. I've checked out a few, they're inevitably loaded with viruses, so you get what you pay for.
Maybe something like Magix would be a good starting point for basic MIDI stuff.
http://www.magix.com/au/music-maker/
You could pick up a Presonus DAW fairly cheap, $30:
http://www.ebay.com/itm/New-PreSonus-S1-Artist-2-0-StudioOne-Artist-2-Music-Production-Software-Mac-PC-/231584863104?pt=LH_DefaultDomain_0&hash=item35eb889380
Presonus site:
http://studioone.presonus.com/
You sure won't need protools yet!
Cheers