Game keeps freezing

For the past few days, I've been having issues where my cursor will either become jumpy or freeze up entirely. I play in windowed mode, but I never have any issues when I play league itself, just TFT.

Today, I try to start a game, get through the queue and it starts to load into a game, when the whole thing just freezes before the loading screen. I've tried to get back into the client three times now, and the same thing happens, the game freezes up, causing me to have to restart my computer.