My gauges are going nuts after driving for awhile. The hand brake and Oil and other lights are on and then the Speed, RPM, MPG, even TEMP goes down and then goes back again. It does happen frequently but it doesn't seems like it has any pattern. I think whenever I pressed brake or gas it happens..but then again I need to take a closer look at this problem.
Does anyboby have a idea?

I suggest you start with basic electrical troubleshooting. Is your battery in good shape? Check your battery cables (at both ends!) and make sure they are securely connected. Try pulling, inspecting, and re-installing each of your fuses. If you find any corrosion replace the fuse. Look for the big connectors where the parts of the wiring harness connect together (there is at least one near the fuse box). Carefully disconnect, inspect, and reconnect. Maybe you will be lucky and one of these things will fix it (especially the battery and battery cables).