What type of processors are in these boxes? What is the word processor? How much RAM? What is the Hard Disk size? How much free space? Have these systems been defragmented recently?
I have seen these types of errors under Win9x and W2K usingOffice 95 or 97 when there were indeed low resources because the user had either not enough RAM, specified a small swapfile, used partition magic to shrink C: and expand D:, or not defragged in ages. Also, Win9x has some serious memory leak problems. Apps don't always release memory after they are closed.
Kill the office startbar. It's a memory hog. It will load office apps into RAM and not unload them so that MS-Apps appear to load faster.
Make certain that you have the latest Service Packs and updates for your operating system and aplications and run some diagnostics on the RAM and Hard Disk to gauge their performance.
Since the last thing that you say was installed was WinGate, uninstall the app and see if the behaviour continues. If not, re-install it and test. It may be something with the configuration of WinGate. If you're getting an error message like "RPCSS.exe/System Resources Low" check out
http://www.deerfield.com/support/WinGate/kb/index.htm?a=1372