It is a common misconception that RAM and system resources are the same.
System resources is a portion of memory reserved for use by the Windows kernel.
Windows 9x/Me is a 16bit OS. ok its a hybrid 16/32bit.
This gives it 2^16 = 64kB
This 64kB is used to manage programs. When a program is opened, some of this memory is used. Ideally, when the program is closed, the memory should be given back. Some proggies, including Office, do not give back this memory. This is referred to as a memory leak. After some time (usually about one to two days), the 64kB pool will become full. Newly opened proggies will not have any space to write to, and the system becomes unstable.
Windows NT/2k do not suffer from this as it is a fully 32 bit OS. 2^32 = 4GB. You will run out of memory before running out of resources in NT/2k.
Switching to Windows 2000 will definitely cure your problems, but an interim measure can be a severly tweaked clean reinstall of Windows ME. (98SE is my favorite 9x version)
With 640MB of RAM, your system should be quite snappy.
I use the following tweaks in 98
in system.ini under the[386enh] add the line
ConservativeSwapfileUsage=1
this will force windows to use all the available RAM before using swap file.
Under [vcache], add the following lines.
MinFileCache=0
MaxFileCache=0
Everyone recommends setting the max vcache to 25% of RAM. I recommend zero. I have noticed increased stability and speed with this setting. It is sad that I cannot find an equivalent setting for Windows 2000.
Windows Tweaks and Retro Drivers