Win7 hangs at startup / won't go further than 'Starting Windows' scree

Hello,

This morning I tried to start my Acer Aspire M3710 (had used it yesterday without a problem), but it wouldn't boot. Everytime I got to the 'starting windows' screen, the screen froze after the animation had finished.

I've since tried restarting in safe mode (hangs at disk.sys), last known good configuration,... - to no avail.
I've tried startup repair - to no avail.
The error message I got started like this:

Problem event name: StartupRepairOffline
Problem Signature 01: 6.1.7600.16385
Problem Signature 02: 6.1.7600.16385

I am now trying the Seagate Seatools to see if there's a hard drive issue. Short test wouldn't run, so I'm trying the long test, but I wanted to already post this, so that if I would be taking the completely wrong way to tackle the issue, you might be able to tell me to approach the issue differently.

The PC is less than two years old and hasn't been connected to the net for half a year (ruling out viruses e.a. in my opinion).

If any one of you might have advice on what to try, that'd be awesome.

Thanks in advance

The long test failed as well, as did the subsequent short test. Does this mean my HDD is, well, broken?

I tried making a Win7 recovery disk to start up from, but that yielded the same results... I haven't got a clue.