I have made a movie from MP4s shot on a camera and I want to export it to MPEG4 to play on the web, but the default settings for the MPEG4 are really small - 176x144 - and i need them to be 512x288 at least. When I try to change the frame width and height the message says I need to lower the frame dimensions/rate or increase the profile - I have tried doing both of these but I still can't get the quality high enough.
ARe you using H.264? If so, try some of the other presets or use the video aspect ratio. the 176x144 is a mobile phone profile.