It should NOT be skidding. From your description I think you are mis-interpreting the "skid light." An '04 Highlander is equipped with an ABS system and the fact that it skids at all is indicative that it is not working properly. The "skid light" that you refer to is actually a warning light that indicates that the ABS system is malfunctioning! You should be getting it to a mechanic or dealer right away to have it fixed.
Yes, they are known as dual-filament bulbs.
It is in the dashboard cluster along with all the other warning lights.
There is no 'set' answer for this question. Be aware that there are built-in warning devices on the brakes. When the pads are low you will begin hear a screeching sound whenever you apply the brakes. When you start hearing that sound consistently - it is time.
There really is no way to give a general answer to this question. Too much depends on where you live - and your driving habits.
The 2004 Toyota Highlander has 16 valves.
The 2004 Toyota Highlander is a gas-powered vehicle.
The 2004 Toyota Highlander has an inline 4 engine.
The 2004 Toyota Highlander has a 4-speed automatic.
sounds like your brakes are not releasing properly
The 2004 Toyota Highlander runs on regular unleaded.
The 2004 Toyota Highlander has a 27 degrees angle of approach.
The 2004 Toyota Highlander has double overhead cam (DOHC).