WHat is the best way to adapt a BNC port to a TP plug?

I installed years ago a coax/BNC network in my house before the walls went
up. Each room has a BNC/Coax port. As opposed to rewiring it all to Cat5e,
ripping things in the process I'm sure, is there some kind of adapter or
something to convert or hook up a TP/Cat5 plug? Not looking for speed
really, just a way to connect for email and messaging.

On one node, I did connect a Linksys router with a BNC port so that I could
connect this to a DSL router. Would this be a better option, connect another
router at the other ports?

I would like to know all my options available.

Thanks in advance!