I'll thoroughly look through every piece of software that's running to 
see if I can turn eveything off that might be causing the problem.

Were you able to reproduce the problem with my original script?  I'm 
sure you have all of your virus/searching/etc. stuff turned off, so if 
it reproduced for you, then those things aren't the problem.

Question: If you take my original script and add joins at the end so 
it's proper and modify nothing else about it, does it show the rollover 
error?

If so, then I think that is where we need to start since you then have 
a simple test that manifests the problem without virus scanners (etc.) 
that might taint the issue.  Then you can chase this without having to 
assume what my system has running on it.