Why wont java download for me?

so i was installing a texture pack for minecraft and when i pressed the link the it to me to IVivid and when it was downloading i shutdown my computer and when i turned it back on it was installed so i uninstall it and a lot of my programs uninstalled with it! so i was like WTF? so i do system restore and it didn't work. So yeah then like i was going to my minecraft.jar file but when i open it, it goes to what do u want to open it with? And that never happened to me, and my friend told me to install java it will work so i am trying BUT when it is like 1 second away from completing it stops for like 1 minute and restarts the download and then it says that the download failed. So why is that happening! Please answer as soon as possible thanks.