A few weeks ago I commented I had found a very promising lead in trying to find out the cause of my performance problems in Windows Vista, in the services/drivers for my simple Microsoft Lifecam VX-6000 webcam.
I can now say that indeed disabling this service has caused a dramatic improvement in performance and responsiveness, and since disabling it I haven't experienced the "machine locking paging frenzy" I was constantly running into.
Now that I feel more confident about the machine not locking up (and now that I resolved my bluetooth issues as well), I've also gotten rid of the pagefile and I switched off Aero and I'm using Vista Basic. It's not as nice looking (alright, the light blue window borders/backgrounds are as ugly as they come), but the machine definitely seems more responsive. It also helps that once you do this you get rid of dwm.exe's memory eating disorder (and yes, that's another process that loves to page a lot).
All of this definitely makes living on Vista a lot more bearable (though by no means a WOW experience or anything). Oh well, at least this way I don't have to give up Spider Solitaire yet ;-).