i found a easy solution to this,all it is a series of clicks.i originally had this problem after i started to overclock my 6970 and i found this,after reading it,it made me aware that this could be a minimizing problem.so here is the steps to do it.

1.Have GUI miner open in the task bar (double click it or right click and hit restore if it is in the tray)
2.Now here's the problem,GUI wont show so what you need to do is take your mouse and hover over the Bit-coin (BTC) symbol for GUI in the task bar, a sub menu will appear and it will have a little red X
3. right click the sub menu and there is options to maximize,click it and the entire GUI miner should fill the screen so even if it is in a small location of the screen,it will fill it up so you can have access to it.
4.now i will be honest I'm not exactly sure if this step is necessary since i cant recreate the problem right now,but this is what worked for me go to options and click "start minimized"
5.Then go to file and click save settings (Number 4 might be able to be skipped,someone can test it if they want   now completely close GUI ,not minimized lol then try to open a new client and see if that fixes the problem. In theory what this does is overwrites the poclbm.ini file and puts in a correct settings you can uncheck start minimized after you click save settings if you want

i found this solution within 5minutes of looking,so if it doesnt work for you then please try everyone elses i just think this one was the simplist and most straight forward one.