Regarding the radio is the antenna hooked in the back of the unit correctly? Is so then your first and second problems are properly due to wires being crossed up. Recheck your wiring diagram closely. Find the CD wires and the speaker wires and tie them together and out of the way. Then begin changing two wires at a time until you fine the correct matchup. (Just because you have two blue wires it does mean they automatically go together) I had this problem in the past.
The only direct fit is what the factory installed.
NoNo
No, remote start was not a factory option in 2000.
Cherokee Laredo, no. Grand Cherokee Laredo, yes.
dealer has to do it with factory scan tool
pull the 15 amp fuse in the fuse box.
The factory size is listed on the label on the driver's door jamb.
There where about three options from the factory. 3.07, 3.55, and 4.10.
There is no such thing as a 2002 Cherokee Laredo. The last year for the Cherokee was 2001, and the last year it came with the Laredo trim was 1992. I have a 2003 Cherokee Laredo so this awnser makes no sense at all. Do you have a GRAND Cherokee Laredo? Those are still being made. They are not the same as the Cherokee.
Yes, Laredo is just a trim package.
Jeep did not make a Cherokee Laredo, they did make a grand Cherokee Laredo, and you can fit 31 inch tires.
yes There was also a Laredo package for the XJ Cherokee in the 1990's.