Lenovo D400 Won't Boot - Upgrade To Whs2011 Or Just Build New?

I apologize in advance for the long background in this post, but it may be pertinent to how you can help.

When my Lenovo D400 was about a year old, I had the OS drive fail and after much warranty troubleshooting (over the course of a month, they sent me a new power supply, a new motherboard, and new RAM for me to self-install).  Finally, they sent me a new HDD for the OS and after a reinstall things worked great for about another year.  I wasn't very happy with many of the limitations of WHSv1, but I liked Drive Extender enough to not care that I had to do manual backups of my Win7 PCs.

Then a little over a year ago I had a 2TB data drive start to fail, completely choking up the OS as it could no longer properly "balance" the data between drives.  I shut down the D400 and removed each of the disks to copy as much of the data as I could to other drives before it could be exposed to further risk.  I wasn't able to save everything from the failing drive, but I got over 95% of it over the course of about a week of "negotiating" with it.

After that I put the OS drive back in by itself and "removed" the data drives so I could reintroduce them as new drives.  Perhaps I should've reinstalled WHSv1 prior to that, but it appeared to let me do the "remove" and "add" process without a problem, so I left it at that.  Having put so many hours into it at that point and having a life that I had to live, I wanted as little to do with it as possible and slowly moved most of the data back over to the D400.

Unfortunately, the D400 has never been the same since then, and I've gotten various warnings about approaching failure and then having the warnings go away.  It would take 10-15 minutes to get into the Console, but when I would check the Health and the Status it would always report "Healthy" or "Good".  Nonetheless, I began to notice that the WHS would go offline and be completely inaccessible about every 2-3 days after a restart.  I proceded to remove LightsOut from all the client PCs and it seemed like I would get 3-4 days between needing hard resets.  Nonetheless, every time I went into the Console it would report that everything was fine and normal, and I didn't have the time to go any further into it than that.  I knew something wasn't right, but I chalked it up to incompatibilties between Win7 and WHSv1 and figured I'd just live with them until I
couldn't get to the data via WHS at all.  Well that time finally arrived two nights ago.

For some time I've had my mind on building an HTPC of sorts that had about 6TB of storage for multimedia purposes and could also serve as shared data access and storage.  This could potentially end the frustration I've had feeling like I was wasting too much time dealing with mass storage on a "computer" that doesn't have a KVM (keyboard-video-mouse) interface or the ability to go into the BIOS or to start in safe mode when it won't properly boot.

It's not so much that I don't like the D400 - I really do in many ways - especially when it was working in virtual silence for months at a time with nary a problem.  I have Streambaby installed on it so I can easily stream to any of the 3 TiVoHDs we have in the house, and that has worked out flawlessly.  My biggest issue is really that the D400 is a real pain to troubleshoot when there's a problem.

So that finally brings me to my dilemma and my questions.

If I stick with the D400, I believe I would go straight to WHS2011 and plan to buy DrivePool to take the place of the missing Drive Extender.  What I don't know is how easy it is to install on the D400 since I would be putting a new drive in it.  Would I have to install WHSv1 on it first so it would boot and then do an upgrade, or can WHS2011 be installed on it without an OS being booted?

The other - and admittedly far more costly - option would be to build some kind of storage server myself (HTPC?) where I could have real KVM access and put almost any operating system on it I might prefer.  The questions here are, would it be worth it? and would I want to put WHS2011 on it?  Remember, I'm looking for a combination of set-it-and-forget-it as much as possible while still having a reliable, empowering, yet user-friendly interface.

What are some recommendations?

Thanks!