After looking at your various reels via google, none of them seem terribly suitable for a 5wt rod, being sized to hold 6-7 weight lines. I guess I would go with the one that's on the rod- if it's smooth running. Were it me I would head to a fly shop and seek their advice as to whether the line on it is suitable. Kinda hard to diagnose via the internet. Again, were it me, I would start out with a 5wt WF (weight forward) floating line to learn with against bass/pan fish in a pond. Intermediate/sinking/sinking tip lines are great for getting a fly down deeper if necessary, but so is a tiny wrap of lead putty on the leader ahead of the fly or better yet use a weighted fly (but that throws off the casting rhythm- best avoid that until you have the hang of it).
Lines can be old and still good- if properly taken care of, and if they were quality lines to begin with. I have a couple of old first generation Wulff Triangle Taper lines that are still going strong 25 years later.
If the leaders/tippet materials have any age to them, replace them- they're cheap. UV degradation will kill that fragile monofilament. Tippet material is the last thing I would economize on.
Methinks you're off to a fairly good start. Like I told a kid's mom who was looking to outfit him for fly fishing- "If he masters fly fishing, he'll master his soul."
