Here's the situation: we're talking about an HP Pavilion laptop. Until about a week ago, all had been normal. Then, with no warning, just after startup, I get a blue screen telling me that an attempt was made to write to read-only memory (can't quote the entire screen; far too lengthy and transient). It then dumps the memory and re-starts. Upon re-start I'm offered a choice between trying to repair or start normally. The former is futile since I get messages saying startup repair is not possible. The latter leads to another blue screen that says "DRIVER_IRQL_NOT_LESS_OR_EQUAL"...whatever that might mean. That is followed by another dump and the cycle begins again.
I've tried starting in safe mode without networking or anything else. That gets me a list of Windows files loading, followed by that second blue screen described above, a memory dump, and an automatic re-start, so that avenue is closed.
So: what do I do now? Am I right in guessing that about all I can do is wipe the hard drive completely and install from scratch? And is there some way to wipe the registry as well so the system is completely clean? (I'm not worried about what files might be on this machine: it's a second machine used for travel and whatnot, so there's nothing remotely critical here.)