88 Mustang sputtering and fuel/oil gauge

Hi,
 
I have an 88 Mustang Conv. and I am having a few issues. First off my fuel and oil gauges are not working. I looked at the fuses and they all seem to be ok. Secondly my car is sputtering quite a bit especially when I am stopped and try to go again. Thirdly, it doesnt seem like it wants to stay in the right gear. It will get to fourth and then go back into third and it does the same with the 5th and 4th. I will let off the gas and it will change gears but then it will do the same thing. This is my 4th mustang but it is the only one I have had issues with. Also, I dont know much about cars so I dont want to take it into a shop and have someone tell me whatever just to get money out of me.  So if anyone has had these issues before or know what it may be I would greatly appreciate it. That way I hopefully will look a little less stupid when I take it to be checked out haha
 
Thanks so much,
 
Angela