XP SP3. Equipment is old. Recently replaced the hard drive and loaded much faster, but the problem is different. 6 MB get in the middle of the game. That in the end will be - it is terrible to imagine.
Okay, so it looks like an I/O problem. Let's try to reproduce it.
The oldest and slowest drive I have is Seagate ST380817AS, 80Gb from 2005.
Aaand... loading the save you posted took all of about 3 seconds.
Since repeated loading of the saved game took about the same time, it's not I/O bound at all.
So, pray tell what's the actual hardware you use. CPU, MB and HDD models, what kind of RAM and how much you've got?