Crash and burn, baby
Windows has presented me with numerous problems. Initially, SL kept crashing one me, due to Microsoft's downright despicable business tactic of breaking all existing OpenGL drivers. (Seriously MS, we all know it wasn't an accident... you should at least have made it look like DirectX was affected a little bit too...). I believe this issue has been the cause of more than one BSOD too. I didn't even think those things we possible in Vista! So much for stability.
Other such problems include various system software components crashing for no apparent reason. The COM Surrogate is the popular one... and yet the system doesn't stop or break or even slow down without it... it just complains, and that's it.
Need... more... foobar...
Oh, and don't get me started on the auto-updates. Now I'm sure my university's firewalls don't help the matter, but Windows update did work. Now it likes to spend all day complaining that it can't. And what's worse? It can't even figure out that it can't update sometimes... it just sits there... and sits there... trying to download... but oh, failing so terribly badly.
Whoops... was I not meant to switch that off?
How about networking? My university is known to have occasional network problems, so when my Internet connection failed towards the end of a day, I called it quits and finished off my work at home. Next day, still no connection, even although every other PC in the room was fine. I tried to "reconnect" and "repair" and all that jazz, to no avail. I was ready to call the tech support, when I decided to check one last thing. Lo and behold, buried away in the system settings, the NIC had been disabled. HOW????!?!!!!! WHY?????!!!! It must have just happened while I was working, with no warning. Even while trying to reconnect and repair the connection, Windows didn't think to tell me "uh, by the way, the network card is disabled". Duh!
Error: you need to be you to continue
So what is there to say about permissions? Administrator access rights? Well, I'm happy to say Windows like to run a tight-ship in that regard... even logged-in as admin, you need to confirm various actions before they happen. Unfortunately, it doesn't always work. I am the only user for this PC, and I'm an admin user... i.e. the only admin user (or so you'd expect). One day, while trying to move some files, Windows refused, telling me I needed admin rights to perform that operation. It wouldn't let me edit my own files because I didn't have permission to do so... even though I had created them just a second before. Even logging-out and back in didn't help... I had to reboot completely. Why can't it just adopt the *NIX approach to permissions? Much more robust.
Analysis: fully-functional. Response: break it.
And finally... audio. I remember hearing the horror stories of audio in Vista months before I got the new PC. I didn't think much of it, as I'm not too bothered with all the fancy effects. The thing is, I do expect the audio to work. I don't have speakers, as I'm in a shared office, so I used headphones. If I forget to plug them in before I boot up, I get no audio. If they are unplugged when I launch a particular app (e.g. SL), then that app has no audio. And now, on the odd occasion, Vista just pretends my headphones aren't there. I can disable/enable them, un-plug/re-plug them, and everything else, and Vista sits there quite happily acknowledging all my efforts, but stubbornly refusing to make a sound. I would guess its internal software mixer is the problem, and it's determined not to mix audio for a device it's convinced isn't really there... even though it tells me it is...
Conclusion
AAAAAAAAAAAAHHHHHHHHHHHHHHHHH!