If you still regularly use your landline, or people rely on your landline for getting in touch with you, then it is absolutely worth keeping it. Many people still do so in order to keep in touch with loved ones, and many broadband deals come with a home phone service anyway - so you might not see any use in discarding it. However, if you rarely (or don't) use it at all, and you're absolutely sure everyone can still reach you on your mobile phone, then there shouldn't be any harm in disconnecting it, or searching for a broadband-only deal that doesn't require a phone line.