While idling, the engine begins to rev to 5000+ rpm any suggestions?

The very last suggestion is definitely not it :) The accelerator is unobstructed...the other thing is that the car has a habit of 'lurching' forward when at a stop light as well. This only happens occasionally, but if the brake is not engaged fully, there is a possibility of the car moving forward. I appreciate the suggestions! As I am not familiar with this car (it's my girlfriend's car), I will look into these-additionally, I don't believe it's the linkage, as this appears to me moving freely. I haven't had the chance to get a diagnostic reading as of yet.