Like the other answers, it depends on what you scanned and where you scanned it from.
If this is your personal computer and you scanned it from your local network or scanned localhost from your own machine, then you shouldn't probably have any of those open unless you are serving on those ports.
If this is some sort of a server (which it doesn't look like from your question), then probably its is legitimately offering those services.
If its your personal computer, I am intrigued as to why are these services open at the very first place. Since you are listening on 80, did you try putting your IP address on the browser to see what comes up.
It is pretty normal for a bot to install lightweight http/ftp/smtp servers on infected machines and serve content, send emails etc.
Just try putting your IP on the browser address bar to see if there are any surprises in waiting !!
To answer your question, your ability to browse internet will not be affected if you close these ports.