Wires, unless they are corroded or burnt, do not get 'old' and do not need replacement.
Semiconductors do not need changing unless burnt.
Resistors are about the same. Leave them alone unless burnt.
About the only thing worth changing are the capacitors, especially electrolytics.
If you have them, another type of component also worth changing are relays and mechanical switches. Their contacts do oxidize and changing them may be a good idea.
If you have surface mount components, this whole thing becomes a difficult task.