I have no heat on my 2008 santurn vue what would cause this

This does not make any since. You come to a stop, then it will not go forward until you hit the brakes, then it will go? When you changed the filter did you set the emergency brake? Sounds like you may have brakes that are sticking when you come to a stop.

i'd start by checking the transmissioin fluid level follow this link for a video showing this , its a bit boring but does show the procedure
Transmission Fluid Level Check Saturn Outlook 2007 2010 2008 Saturn...

check for break in the wiring at your trunk/boot.

Check levels if fine and not over heating clear the engine light sometimes changes in level will trigger it. If light comes on again after adding fluid. Then you know its something further but unlikely if it hasn't been over heating. If your losing fluid you might want to check around pump to make sure gasket seal is still good or check and make sure plastic turn opening valve on bottom of radiator isn't loose.

1. Switch off the car
2. Pop up the hood and raise it
3. Locate the transmission fluid cap
4. Remove the cap to add fluid
5. Check the owner's manual on what type of fluid your car requires and in what quantity. It is essential to use the right fluid and not anything off the shelf.
6. Remove the dipstick and start filling up the fluid slowly - you don't want to add too little or overfill.
7. Now put back the dipstick, switch on the vehicle and start shifting gears. Remove the dipstick and see the marking to know if you your car has the right amount of fluid
8. Put back the cap by turning it clockwise.

A failed air temperature control blend door motor or sticking door or a failed stuck open engine thermostat.

Go to a dealer or junkyard.

the dipstick is located behind the front transmission mount and its held in by a 12mm bolt. you may need to remove the transmission mount to check the fluid. the color of the dipstick is yellow, make sure the car is in park and fully warmed up to operating temerature and on a level surface before checking the fluid.

Here you go..

Be sure that transmission fluid temperature is at least 104° F (40° C). Models with 2.2L engine: To access check/fill plug: In the engine compartment, remove clamp from air hose behind cooling fan. Separate air tube from the hose and push the tube back towards the transaxle. Remove the clip holding the two power steering lines together. All Models: From underneath vehicle remove the transaxle check/fill plug with engine running. Fluid level should be even with hole. Add fluid as needed until fluid flows from hole. Replace check/fill plug and torque to 9 ft. lbs. (12 Nm).