A. Those tubes are terrible, and the wrong size for your tires. Go to your LBS and get the proper tubes for your tires.
B. The bike needs a good tuneup. Take it to your LBS and have them tune it up for you. It may need cables too, and if the original owner really did assemble it himself he probably didn't do it right based on other things you've described. Tear it down to the frame and reassemble, being sure to grease everything properly.
C. Sounds like the wheels are over tensioned. They need to be detentionsed and then retensioned to spec and retrued. Take it to your LBS.