Stick with my old account?

so wouldn't that disable the search from the start button? like start then just typing in the process name / file name to find the file? if it does disable that, how much does it improve performance or longevity by?

No, It doesn't disable it, It only means it'll be a little slower when searching. It honestly doesn't need to be on, it just wastes resources.

Im not sure of the exact figures, But it's better to err on the side of caution and do whatever will keep your HDD the longest. HDDs are pretty easy to burn out honestly.