Low System Resources

Running Win98SE,Intel Mbrd,128mb Rdram,40GB IBM HDD.
Problem:
Achieve 85% free system resources on boot.
Open IE5.5 & Outlook2000 for a short while & resources drop to about 60%.

I have tried serveral memory managers but none seem to permanently solve the problem.

I wud really prefer to come up with a solution thru Windows if at all possible.

Thanks for yr feedback/advice.

Peter Grimes