What can I do about my poor wifi connection?

All those things may help.

First, get a higher Internet speed from your service provider. However, with just that, those watching streaming video will gobble up even that bandwidth in short order.

Next step is to get a better router that has some form of bandwidth control. A lower end form of bandwidth control is QoS, but it does not control bandwidth that well, but instead priority

(who gets priority for traffic)

. Also, make sure the router has higher end connections (AC modes and 5Ghz connections). Better wifi technology only helps however, if the laptops have matching capabilities.

Lastly, forget wifi and run a wired connection if you can. If not possible, look into Ethernet over Powerline adapters. They provide reasonably good speeds, are wired directly to the router and your PC, and are not affected by the wifi traffic.

Any one of those things may help your speeds, all of them helps even more.

A "Range Extender" might solve your headache. You can generally find them on amazon.com for $20 or so. It simply plugs into a wall socket, grabs the available weak signal in that room and then amplifies it. It may do the trick since your problem may be a weak signal as opposed to the rest of the family using it. HOWEVER ... since you have cable, and everybody is home currently, it may be slow because everybody in the neighborhood is home also and using their computers. You might want to keep some notes and do speed tests at different times of the day to see what times are the best to be online based upon how the neighborhood is using all the bandwidth of the cable.

go into netflix account and set streaming quality to 720...that should help

You could read a book.

Just a thought.

Fibre optic connection (cable if available) and an up to date router should transform your situation. Search the net for deals and look for speed and unlimited downloads.