Disable wireless signal on router/modem?

First off, smart move going wired. Wireless is convenient, but you will get a better overall connection when plugged straight in.

Removing the antenna won't disable your wireless features...it will only make the signal weak.

To disable the wireless, you'd need to log into your gateway and change the internal settings. However, this procedure can vary depending on your hardware, so I'd need to know a little more about your ISP and what kind of modem you have to tell you specifically. You could either consult the manual for your gateway, or email me the details and I can help you more...

I'm digitalhigh@ymail.com.

Those are not really slow connections for the average broadband connection. It is more likely that your new computer is relatively slow. If it has a slower processor and not much memory web pages will not load very fast and the computer will be slower overall. The 5735z is definitely not the fastest laptop out there. It could just be a low quality wireless card. Make sure you have the router set up correctly. It should be running in g mode at the minimum.

If you're not using the wireless, disable it completely. Wireless is useful but is inherently less secure. Don't take the risk unless you have to.

In the future if you get wireless devices and choose to reenable it, at a minimum setup WPA encryption to keep the connection secure. I've also seen some routers that had the option to give wireless devices access only to the internet (and not any access to the rest of your computers on the wired LAN). If you just want network access this is a good idea, as worst case scenario someone who hacks your WPA key still can't get to your internet computers.

Make sure you change the default password on your router too.

Either. Removing the antennae will definitely stop the signal from being broadcast. If you are worried about security, though, the best way is to either set up a secure password or disable wireless completely. Either would be done from the router config page, typically reached by navigating a webpage to its internal IP address.