Appreciate the suggestions, folks.
The system is very clean, but there are a lot of processes running (by choice).
I use the computer several hours a day, and my heavy-duty surfing warrants a lot of security features. I have several layers of security.
I use Ad Aware, Spyware S & D, and Spyware Doctor, and find Spyware Doctor the best by far.
In addition to the anti-virus program, I have a resident five-star commercial anti-Trojan program, another resident commercial anti-logger program, and a few other goodies.
The drive is always defragged. I use Diskeeper, which runs automatically at night, and I usually manually defrag at least once during the day. Once a week I run a boot-time defrag.
I used to manually tweak the system using the items from Speedguide.net, but now I use TCPOptimizer.
My desktop is directly connected to a Netgear 108 Mbps wireless NAT firewall router, and two other computers are connected wirelessly. Each computer has a software firewall.
I have a resident VPN encrypted tunnel program running constantly, as well as a resident remote-access program.
So in view of all that is running, I am happy with the performance. But I always am looking for improvements, so thanks for your suggestions.