Does your wifi require a password?

doing something, there is a pw for Admin? functions, which I have written down & never use for daily use.

Do you need to give them a passphrase or password to connect?

Machinery here.

which is one reason I stopped using it, not because it hogged memory, though it did that too, but because every time I opened it it was either downloading, installing, or asking me to clean up after update 48.053, meaning I needed to screw around with the extensions it kept breaking.

Anyway I've had a lot of luck with Opera, which has its own ad-blocker that works as well as any extension I've tried and ten times better than IE respecting ads. It's very simple and apparently based on Chrome which I've also tried but like less:

http://www.opera.com/computer

This tool will let you see whats/whos on your network: http://www.nirsoft.net/utils/wireless_network_watcher.html

If you stream alot of media,your router will get laggy over time,I reboot every few days and do a save config, factory reset monthly+ and put the config file back in.It definitely helps.

Good article here(with links) to stay fast :http://lifehacker.com/5931743/top-10-ways-to-boost-your-home-wi-fi/all

Its not Firefox causing it.

that "errors" *DO* show up for last evening when I couldn't get a connection to send and e-mail, that it isn't a matter of somebody using my connection so much as possibly MALWARE.

DUers have previously suggested I use MalwareBytes, which I did on a free trial, and this tech this morning said I should try it again this time. My anti-virus/Trend Micro is always doing scans and showing nothing.

So, am going to try the malwarebytes for now.

...in your Router's admin screens should give you an idea as to who has/is connecting. You can assign "reservations" for IP addresses based on MAC Address (they look like BC:22:F4:2C 4:FE), then when someone new connects they will get an address assigned outside of your "approved" list of connections. You can even configure the router to only allow MAC Addresses that are on your approved list and deny others that are not on the list.

Depending on the router, some manufactures give you statistical screens that show bandwidth usage over the course of the billing cycle. That would be one way to easily see which device is sucking up the usage. I highly doubt that someone connected to your wifi could disrupt your connectivity.

I second this advice. Check the Mac addresses for all your devices and only allow those to connect to your router. It might take a few minutes to setup initially, but then it should work fine until you need get some new devices to add.