Your toilet is not as scarry as you might think, some people tolerate the drips, the running all the time and the refilling of it every 15 minutes. There is only so many things that can go wrong, so if you are fortunate enough to have a good old fashioned 2.2 gallon flusher, hold on to it and fix it.
I will try and explain the basics of how to do what needs to be done and try to get it in proper working order again. Without hiring a plumber.
There are many different brand name toilets, the most popular are, Kohler, Crane, American Standard, Toto, etc...
I have to give this site credit, look at this great demonstration
on how the siphon action works. howstuffworks.com
Recently we were having problems with flushing, I changed everything, the ballcock assembly, the flapper valve etc and nothing seemed to work. Then I remembered what an old Plumber friend said to me. If the rim holes ever get plugged up with calcium or mineral deposits the toilet will not flush properly. Just clean them out. So I grabbed my wifes little mirror and found all the holes and cleaned them out with a little screwdriver.
The toilet is back to normal because I dug out little pieces of hardened mineral and calcium deposits. Flushed a couple times to clean them out, it only took 10 minutes.