Client flickers, can't minimize, will crash during champ select [client][crash]

The client will flicker at random times which causes a temporary lapse in screen action. Examples: if I am typing in chat and client flickers it will stop my typing and require me to re-click on the chat to begin typing again; while I'm selecting runes and masteries if the client flickers whatever selection I attempted to make will not go through; and the same will happen while selecting champions. However, if the flickering happens and I repeatedly click the client will keep flickering and crash. This can happen during champion select and not kick me out of the select. I have been kicked out of the champ select twice this way and both times logged back in to a reconnect message and entered the game. When I am in a game while playing in full screen mode I can no longer minimize. If I do minimize I cannot simply click the program on my dash because it will not let me in. If I try to right-click and select the game manually it gives me this message: (see attached screenshot)
The only way for me to get back into the game is to use task manager to force close the client then re-log. The reconnect button will appear sometimes before I force-close but the button does not work. I have tried playing in windowed and borderless modes and I can cycle through my windows using alt-tab. However, in these modes the game flickers just as it does in the client and will often cancel movement/attack clicks and ability key strokes. And also like the client, if I end up button mashing due to frustration the client will crash and force me to re-log. I can get all of these things to occur almost every time I open the client. I have repaired my client multiple times and even deleted and re-installed at one point. Nothing has fixed the issues.