Ununpentium115

Hello, new to the forum. Glad to be here.
I have a '98 Civic Hatchback 1.6 Automatic Transmission.

All the codes and their corresponding effects are present in my vehicle and its behavior.

Here they are:

-p0135 (Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1)
-p0501 (Vehicle Speed Sensor Range/Performance)
-p0700 (detected transmission fault)
-p0720 (Output speed sensor)
-p0141 (Secondary Heated Oxygen Senser)
-p1298 (Electrical Load Detector Circuit High Input)

So, I figure not all can go bad at once. Or at least I hope so.
There must be something that is causing all these to go off. If one or two are fixed the others should go away. Of coarse, I can't be sure so I am asking anybody who can help. If I can fix it myself, that would be great, but if not, any information would be helpful. Just so I won't get ripped off at a shop. Anybody have any ideas? All help is greatly appreciated. Thanks.