As far as your no reverse/shifting issues, 1st things 1st. Check your fluid level and condition. The dipstick is on the front left side looking into the engine bay, and is way down low, under the A/C lines. You may need a pair of pliers to remove it initially. Unscrew it, wipe it off and reinsert it BUT DON"T SCREW IT BACK IN. Pull it back out, and make sure the level is between the two marks. Fluid should be pink to red, not dark, and should not have a burnt odor. I'd recommend changing the fluid anyway, as it is too often overlooked. The procedure is simple; it and other transaxle info. can be found in the service manual section, or by searching this forum.
Can you be more specific about the wheel rubbing? Is the car lowered? Is it badly rusted?? Are the tires the right size, or does it have custom rims?
"Hissing" when removing the gas cap is the release of normal back pressure in the system, and is actually a good sign that the fuel system is holding pressure. Fill it up and forget it.....you may want to poke your head inside the wheel well and check the filler neck and lines to the gas tank, and under the car from the gas tank to the engine just to make sure the lines aren't rotted.