Hey -
I was running a Windows 95 box, then the same system with 98, for two years. I don't know what the problem with my system was, but it had some MAJOR memory leak. I installed a copy of MemTurbo, and was actually able to use my computer. My CDRW drive stopped getting buffer errors, my system behaved more like it should, etc.
MemTurbo 2 is user configurable so that it will try to recover memory every 30 minutes (configurable time period), but this can be turned off -- which should remove that "gaming" concern. Because the system does SLOW down majorly whenever MemTurbo runs. It can also be set to automatically recover memory when it drops below a certain amount -- I can't remember if that's configurable, but you can certainly turn it off.
If you're experiencing slowdowns after you've used your computer for a while, this is certainly a good idea, same if you've just loaded a few programs and shut them down. I haven't used RamIdle, but same idea goes for that. It might not help too much if you only have your computer on to run one program, then turn it off. But overall I'd say it's a good idea.
HTH,
Andrew