Wouldn't that stil be relying on my crappy Wi-Fi though? If the Wi-Fi breaks, then the movie stops?
Niteflyr got it. If your wifi is unreliable because your broadband provider is:
- not delivering consistently robust broadband, the problem is the pipe "outside" of your home.
- delivering consistently robust broadband, the problem is the pipe "inside" of your home.
You can't easily fix the first problem unless you can change broadband providers or your current broadband provider does something to fix their problems.
You can probably easily fix the second problem by getting a better router or better cables, etc.
I'm guessing but I'm going to assume the first problem is the issue. Run speedtest and see if you have robust broadband to your home via a wired (ethernet) connection. If it is robust, go buy yourself a new router and your wifi issues will likely be solved. If your router is pretty old, a new one will bring latest & greatest wifi technology. If your router is pretty new, try moving it to a different position in your home and see if it improves your wifi reception. If it's close to your

TV, connect it to your

TV via a wired connection.
Note too that if you have a newer router but you have lots of people streaming lots of video via that same wifi, there's only so much wifi bandwidth to go around. If you don't have people living with you but you've shared your wifi password with a neighbor(s), they may be eating too much wifi bandwidth.
Once the rented video is downloaded to that computer in full, it will stream as fast as anything else can stream from that computer to your

TV. If you try to do all that via wifi and it's slow, temporarily wire your computer to your router and, if possible, your router to your

TV (cutting any dependency on wifi completely out of the equation).