iMac 2011 issues—status bar on start, volume control crossed out, spotlight not working. HELP!

About every other time I start up my Mac I get a status bar on startupt (before the login). It takes a bit longer than normal to start up but eventually it does. However, on these occasions that my Mac acts like this I also encounter two (at least) other issues. The first is the volume control has a crossed-out symbol, and hence there is no sound whatsoever—internal speakers or external. Further, and perhaps more troubling, is Spotlight does not work; I attempt to search but I only have the option for web results.

I also notice some general slow down and it sounds like the Mac is always working on something (fans aren't running full blast though). This led me to open Activity Moniter, which revealed and absurd amount of Wired memory (about 6 GB out of 8).

What is going on here? I've tried resetting my PRAM and booting in Safe mode; however, I am having the embaressing problem of not actually accomplishing those tasks (I think). I hold down the correct keys but my bluetooth keyboard doesn't seem to be responsive early enough for the keystrokes to register.

Help!