Strangely I am having the same exact issue, except these problems presented themselves just today. I am not sure what happened but any help on this matter is greatly appreciated.
EDIT:
Alright simple fix that worked for me, just go to your Hidden: Source launch options and put in -w 1024, It should open up in that resolution, allowing you to change it to whatever you want.
Last edited by ado921; 8th January 2013 at 00:48.
Reason: Fixed the issue, added possible solution.
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