Any place that sells filters can tell you the correct filter. On your GM product I recommend you use an AC/Delco, Purolator, or Wix filter. They are superior to Fram.
A 2000 Chevrolet blazer with a 4.3l V6 would have come with a spin-on style filter. If you go to your local parts store, a WIX brand filter would be a part number 51036
Yes, there is an "O" ring inside the fittings.
On the oil cap it says "5 W 30".
on the oil pan...
Under the vehicle, lift the plastic door right behind the front bumper; you will need a screwdriver.
Yes
You didn't say which engine you have but Chevrolet's oil pumps are located inside the oil pan.
trans or oil? oil is in front left. i dont think the 98 blazer has a trans dipstick. Instead, there is a bolt on the side of the trans.
10w30 is what I would recommend for a 8 year old engine.
This sensor is at top rear of engine, next to distributor.
Yes you can.