Hosting minecraft server with ethernet cable?

I would recommend you learn about port-forwarding and setting up virtual servers, but I would not attempt this on a low spec computer as minecraft servers can easily overheat any less than able cpu's and cause permanent damage.

Incomplete question, why don't you elaborate in the body of your question?

Even Wi-Fi would work as long as it is consistently faster than your internet connection. The choke point that would typically limit the number of players you can have on a minecraft server at home would likely be your internet "upload" speed, which is usually significantly lower than your download speed.

I've been a Minecraft server host for two years on a One Core, 2GB RAM Windows XP Home and have built up a vast quantity of players. My players where excited to hear about it becoming HARDWIRED, which means plugging it in with an ethernet cable. You should definitely use an ethernet cable. If you need help setting up and maintaining your server, I can help.