An A320 Flight Crew experienced dual frozen FMGC displays while at cruise altitude. They continued to their destination utilizing standby navigation and helpful vectors from ATC.

Narrative

Entering weather data on performance page and FMGC's froze further inputs. Both FMGC's were unresponsive for the remainder of the flight. Captain could only access performance page with the winds remaining in the scratch pad. The First Officer could only access Flight Plan page. Neither pilot could make any changes on FMGC page displayed and could not select any other page. ACARS access was available. Contacted Maintenance Control and they suggested a procedure which only allows a reset on the ground. Neither pilot was willing to attempt a FMGC reset while airborne with potential random results. Advised ATC we had a frozen display and could follow the arrival route in heading. We were able to select VOR's and ILS' if necessary in standby mode. Asked ATC to follow our progress and if any deviations were noted to advise us. ATC was not busy and did not indicate they had any concerns with our request. Captain offered that if any deviations or problems arose that he would declare an emergency; also noted that if a go-around became necessary that declaring an emergency would be immediate. ATC provided vectors to final intercept. Weather was night VFR. Airport was acquired early. FMGC's auto tuned the field VOR and correctly tuned and ID'd the ILS as the anticipated arrival runway was the one we used on arrival. We wrote up both failed FMGC's and briefed maintenance on arrival. Aircraft had experienced a recent failure and replacement of FMGC #2.