The control-alt-FXX should work if you have the ttys available (usually 1-6 are available, though not always). One other thing you may want to check is if your keyboard is intercepting it - I had problems with my keyboard not letting me ctrl-alt-fXX until I discovered a small "F Lock" button on the keyboard. Turned that on and everything is peachy
As for your resolution problems... could be lots of things. Do you have the correct drivers for your video card installed? (If it's an nvidia card, get the driver from their website and follow the directions). Also, make sure you have the right frequencies and stuff set for your monitor (hsync and refresh rates - get these from your manual, or from the manufacturer's website if you can find it).
Edit: oops, sorry, I misunderstood your post. You asked about ctrl-alt-+/-... hmm. That I do not know
Is there more than one valid resolution listed in your config file?
