You wrote:
"Is there any software at a reasonable cost which could help? I know that there are commercial services which can do this but they are too expensive for us. I also reject any trial services which are free to start with then start costing money. Anyone got any ideas?"

My reply was that you would have to seek out such on your own, which you did. But now you see that there are issues. Let me share that most Windows boxes I encounter are usually unstable to begin with. From the resource limits of DOS based Windows which can cause those machines to have finite limits to what can be done and for how long to the continuing story that Microsoft doesn't update your BIOS or supply the latest or most stable drivers for users brings this all to the "finger pointing game." Add overheating hardware or this and that and at times I wonder how people get along.

Ok, let's look at what I consider to be fairly stable systems.

1. No DOS based Windows. Sorry, the 64 thousand byte resources are just going to not be fixed by Microsoft in Windows 3, 95, 98 and ME. These will not do.

The memory article at http://www.aumha.org/articles.htm descibes these memory spaces and what happens as they run dry.

2. If we are to stick to Windows, then Windows NT (any version) is tossed out due to a security issue that Microsoft has decided to not fix. That leaves us with Windows 2000, XP and 2003.

3. Windows 2003 is not an good choice since driver writers are still grappling with the new ways. This leaves us with Windows 2000 or XP.

To get stable 2000/XP, the stock install is performed on a solid machine with latest BIOS and the machine having been known to be XP/2000 compatible hardware. Drivers for motherboard, audio, video and more are found and installed and tests to see if the onboard sound is OK or not may find that a real sound card has to be fitted. Some may revolt at this issue, but then it's a warranty issue with the motherboard maker. USB issues are then explored with the help of the http://www.usbman.com site where again, one wonders why such USB chip issues are foist upon the populace.

After all that, then we try the application.

4. Lastly and most ghastly are the PARASITE issues. No issue like this appeared a few years ago, but today we need to be proactive in educating and removing the pests which Antivirus vendors are frankly ignoring. Read http://www.mvps.org/winhelp2002/unwanted.htm to catch up.

Sometimes those dedicated video conference boxes and services are cheaper.

Bob