Windows 95 crashing problem

Recently, a crash-causing problem has developed for no
apparent reason.

A few minutes after opening an application program (such
as Word, Excel, TurboTax, Quicken), and without
performing any activity in the program, I get the dreaded
blue screen with the message "A fatal exception OE has
occurred at UO28.CO236A11 in VXD VMM(OD)+0 0001A11."

Ctl-Alt-Del does not get me out of it. Have to turn off
and restart computer.

As long as I just stay in Windows and its "Accessory"
programs, including Explorer file shuffling, no problem.

My system is: Pent. MMX, 200 MHz, 256 MB RAM. From
System General I show "Windows 95, 4.01.0.071 B, IE 5
5.0.4807.2300." This is a 1998 up grade from my 1997
Windows CD that came loaded on the computer "MS Windows
95 with USB support." The C: disk has 327 MB free space.

What can I do to correct this crashing problem? If your
advice is to reinstall W-95 from my CD. How can I then
get the upgrade?

Thanks for your help.