EasyCleaner has a registry cleaner AND a function that lets you stop programs from starting up when you boot via the registry.
I've also heard that not using Vsync can cause rubber bullets. Open up the nVidia Control Panel and go to Performance and Quality Settings. Turn Vertical Synchronization on.
I'm running DSL with a 3.06GHz Northwood, 1.5 GB of DDR400 RAM, and a GF6800 with all the shaders unlocked. No rubber bullets, very little lag, and FR from 36-75 (75Hz refresh on the monitor) with 1024 textures preloaded to memory and all sliders set to full.