System Maintenance- If you aren't doing this today, you should be. The items listed (i.e., temp clean up, defrag, disk errors) are all good, sound practices that help insure your system run efficiently. Also of note here is that system maintenance is not a one time thing. Create a scheduled task (it's Windows feature) that runs these utilities on a regular, scheduled basis. SolidWorks Rx does all of this for you (see next topic).
SolidWorks Rx- There is tab within SolidWorks Rx that performs the valuable tasks described within Microsoft's article and also some additional SolidWorks aware cleanup.
Readyboost- I personally would never recommend using non-volatile flash memory as a replacement for adding more RAM to your system. As a CAD user, you need to insure you have enough RAM, and an operating system that can address it, to do your job. If you need access more than 2GB of RAM for all applications you have running, a 32bit operating system will not need your needs. More on this topic later...
A CAD workstation gets pushed hard and needs proper care. If you aren't doing some this today, check out this article or just open SolidWorks Rx and setup regular system maintenance on your computer.