PHP crashing/restarting Apache - PLEASE HELP ME!!

So I upgraded the hard drive on my server installing Windows XP and the newest versions of Apache (2.0.51) and PHP (5.0.1) on the new drive. Everything was working out fine until I realized that several of my PHP scripts were not working with the new setup.

Unfortunately, I accidentally formatted the old hard drive, so now I can't go back and see what was different that worked on the old setup.

I know this: every PHP script that does serious file processing (either parsing a long file or cycling through something like 400 files) will cause Apache to crash and then restart. Sometimes repeatedly so that the browser loads halfway through the page over and over. Sometimes with smaller scripts, after several of these reloads the PHP will work and the page will load all the way. When I look at the Apache error log, I see this for each crash/restart (the child process # is different each time):


[Thu Sep 23 04:49:56 2004] [notice] Parent: child process exited with status 4294967295 -- Restarting.
[Thu Sep 23 04:49:59 2004] [notice] Parent: Created child process 3764
[Thu Sep 23 04:50:00 2004] [notice] Child 3764: Child process is running
[Thu Sep 23 04:50:00 2004] [notice] Child 3764: Acquired the start mutex.
[Thu Sep 23 04:50:00 2004] [notice] Child 3764: Starting 250 worker threads.

I've tried every combination of Apache 2.0.48 through 2.0.51 with PHP 4.3.3 through 5.0.1. I've tried changing all the timeout settings I could find in php.ini and httpd.conf. I've changed around all the fopen settings in php.ini. I'm 98% sure I hadn't changed around anything in php.ini with my old setup. I did have a lot of custom settings in httpd.conf, but would anything in there cause this??

I don't know what else to do. I'm desperate! Does anyone out there have any idea how to get my stuff working again??

Thanks,
Joshua