I stumbled onto this tonight while performing some tweaking of my system. It seems to have increased the simming speed for me considerably (my computer is a P4 2.8GHz with 1GB SDRAM).
-Download
Lexun RegScrubXP. Its a well-used safe freeware program used to clean your registry (I've used it all the time for over a year).
-After installing and launching the program, click on "Misc."
-Select "Disable creation of short names in NT file system (NTFS)."
-Unless its already disabled, click modify to disable it.
-Reboot
-Launch OOTP and enjoy faster sims
I save box scores and game logs. I'm guessing that if you don't save these, there won't be an appreciable increase in sim speed.
NOTE: your files will now be unreadable by DOS and Windows 3.x. I have no idea what the effect is on Linux. But if you use a modern version of Windows, this won't be a problem.