After 5 years, the battery is certainly not what it once was, and if any further issues are noticed it should likely be replaced. It has lasted longer than most do.
The startus interruptus issue doesn't necessarily lead to a blown fuse; since the issue is that too little power gets to the starter, it may never create a draw that causes any fuse to go. That being said, which fuse blew? You didn't mention which circuit it was on. When my Norge's starter failed, it blew the fuse - but then would not start after the fuse was replaced, which led to identifying the starter's death throes as the cause for the blown fuse. In your case, that doesn't seem to apply.
