Hello, I've been playing LoL for a few weeks now and lately i've been getting this problem, while in the mdidle of action, the game minimizes and goes back to desktop, and LoL bar looks as if it was active and i get this red sword for a cursor (LoL cursor maybe?) and alt-tabbing back to the game takes a while. It's pretty weird since it never happened before.

My PC stats are as follow:
OS: windows seven ultimate RC build 7100
CPU: intel core 2 duo E8400
RAM: 4GB ddr2
Video card: Ge-Force 9600 GT

i haven't changed the config of the game nor my hardware lately so i dont really know what could be causing it, maybe the CPU is heating up a lot since these past days here were very hot, i'm clueless.. any help is very much appreciated

Excuse my english, i know it isn't that good