Personally, your Virtual Memory settings are fine.
You simply need more RAM.
I would add 128MB to each system.
Further, you may have memory leaks on some of these systems.
If you installed IE 6 or DirectX 9 on any of these PCs, you may well have a memory leak.
Start by checking for an updated video driver that supports DirectX 9.
If that is not available, you need to drop back to IE 5.5 and DirectX 7 or 8.
Alternately, you can improve performance by installing a memory manager such as MemTurbo.
Another option, is a spy-ware infection.
Download and run AdAware from www.lavasoft.de
Still having problems?
Time for a full fix.
Take one system that is particularly bad.
Back up the data files, and format the hard drive.
Re-install Windows from scratch, and ONLY the applications the user needs.
You may be surprised as to how much faster a clean load of Windows runs.
Other items that can impact available memory:
Large wall-paper files.
Fancy Cursors and Icons.
MP3 and other audio players.
Chas