Welcome to the Apple Community.
The first thing to check would be your internet download speed, you can do this at www.speedtest.net.
1080p HD movies require a recommended speed of 8 Mbps, 720p HD movies require a recommended speed of 6 Mbps, while SD movies require a recommended speed of 2.5 Mbps.
i checked this and my download speed was 9.48mps so why is it taking so long?
Ive never had this issue before. To add to that itunes showed a window that said my movie was ready to be watched, so I opened it to find it not working and when I went back to itunes store it says it will take 23 hours to download. Where is the refresh button on this process. Something is jammed and I would like to start again. Should I restart it?
This is definitely a frustrating issue particularly if movies have downloaded OK before. There can be a number of things that will effect the download speed directly to the Apple TV besides your download speed and they can be random.
1. What brand of router do you use?
Often some brands of 3rd party routers require ports to be open for the Apple TV
2. What security type is it using? - WEP, WPA, WPA2; the Apple TV prefers WPA2
3. What wireless channel is the router set to, as wireless interference can cause this issue.
Most routers are factory set to either channel 1 or 11 and other wireless devices such as: cordless phones, security cameras, baby monitors are often set to 5 or 6. I have found that channel 9 usually proves to be a good choice.
These articles may prove useful, good luck.