Anyone would think running a PC is a constant war with the OS!
I don't keep it efficient... I just don't install any optional software that comes with any freeware. And I uninstall anything I don't find useful. That's the level of maintenance I do - if you can call it that. Kind of like tidying up around you and binning junk mail. What I do have is a machine that is spec'd to a level and not a budget.
I'm convinced when people say their PC is running slow it's because they blindly install applications and accept all the adware that gets run at startup - thus slowing the machine start time to a crawl and clogging the (often inadequate) memory with stuff. Once the machine is up and running, the only thing that can slow the machine down (virus' excepted) is a lack of memory. Well, perhaps Johnny should have paid an extra £50 for the 4GB version of the machine in the first instance....