Truck only starts once in awhile and when it does it seems like its not getting enough gas.

My husband thinks the timing belt needs to be replaced on his 94 Trooper, but I wonder because there are so many different things going wrong. First it doesnt start all the time and we just replaces the starter. It will start with a jump and start again if its started within an hour or so. Any longer and it wont start or he has to keep trying and after about 20 trys it will start. He has checked the battery and its good. All the lights work, it just wont start and there isnt a clicking noise either. Then once started it acts like its not getting gas and is very slow and sluggish, kind of jurks when starting from a stop. It does have a bad transmisson and we need to shift manually, its an automatic. I just dont think putting a bunch of money into such an old car is a good idea. If its a simple fix then ok.