Unusual Problem I get (Please help)

[AsrielUK]

I've been dying to emulate games for awhile now and now I've got an Xbox one controller wired and this emulator, I was ready to go and play some GameCube. The emulator runs very well but it's when I close a game weird things happen. When i start to close a game by clicking [X] I'll notice some icons and parts of my task bar start to go black and I have to click the emulator tab a few times to actually accept the confirmation. As soon as I did that, I'd thought it would be over but every time I close the game like this, my PC seems to lag quite badly to the point where clicking icons and browsing is next to impossible which requires me to (Ctrl + alt + Del) and sign out then log into my PC again. That fixes the lag but I don't really fancy doing that after every time I finish playing a game. Now I'm not exactly sure what the issue is to be honest and my spec seems fine for requirements. Not to mention playing games seem to run very smoothly but it's just during closing the game and after closing the game everything then seems to lag. If anyone has encountered this issue or knows a fix please let me know because I've honestly tried browsing the problem and nothing appeared to show up so I'm very confused as to what the situation is. Many thanks.