Need help reading codes

i went in and got my 96 firebird scanned cause the service engine light was on and i got a couple codes i need help reading and fixing.

first one:
History DTC P0133
O2 Sensor
CKT Slow Responce
(Bank 1 Sensor 1)

second:
Transient DTC P0135
O2 Sensor Heater
Circuit Malfunction
(Bank 1 Sensor 1)

Third:
History DTC P0300
Random/Multiple Cylinder Misfire Detected

Fourth:
Transient DTC P1133
HO2S (Sensor)
Sensor 1
Insuff. Switching

Fifth:
History DTC P1406
EGR Pintle Position Circuit

Sixth:
History DTC P1870
Transmission Comp. Slipping

hope anything isnt too serious. :(

Acouple? Lol

Not exactly sure myself but either your cats are bad, and or the O2s arent working right. All those codes are related though.
http://www.quarter-mile.net/LT1_FAQ.htm
that link might help, good faqs!

this link explains whats going on ,
http://www.v8sho.com/SHO/TSB0197HO2SServiceTips.htm

yeah, just a couple lol. i took it into my friend's dad's garage, hes a mechanic, and he ran my car again for codes with a better code reader. he came to the conclusion that this one thing needed to be replaced. i forgot what he called it. once that is replaced, it'll take care of all the O2 censor stuff. but for the Transmission Comp. Slipping code, he said that the worst possible case is that my torque converter is dying and will need to be rebuilt. that would cost me about 1200$. :( but thats just the worst thing that could be wrong and im really hopeing that isnt the case. he told me he'd check my oil pan or something for "shit". haha. i'll keep updateing later.