I liked Denso wires and O2 sensor from Rock Auto. NGK plugs were OEM. I bought them there also. My thermostats lasted 80k to 100k before they would go bad. I used OEM or Stant. Last I read at Saturnfans a PCV valve that just has a pinhole was recommended. That was the last one I used. They have the part numbers there.
There is a way of telling if you have the new style temp sensor. Something to do with the shape, etc of part you can see after installed.
RE: oil change. It was a mess. I cut a plastic jug and put it over axle to divert oil past the axle. It did help keep the axle clean. I eventualy went to an extended size oil filter (Fram 3600 or equivalent) and changed the filter every other oil change. It seems like Fram Ultra would be up to this task.
When you do the wires remove the coil packs. Make sure the terminals are clean. There is a metal plate where it mounts to the engine. Remove that and clean it with Scotch Bright. I applied a little dialectric grease. Bought my car with 71,666 and by 75,000 had a weak O2 Sensor and dealership picked up a misfire. It was caused by that plate for coils getting corrosion.
While you are getting things done you may want to clean the EGR and throttle body. I installed a Klean screen on the EGR after the pintle stuck open and would hardly idle. Almost got stuck 30 miles from home the Klean screen kept this from happening after cleaning.
EGR Klean Screen
If you ever need a transission mount, torque struts (dogbones) or top engine mount use OEM. Never every use Anchor aftermarket on transmission and dogbones. I lost several good years off my car after I installed them. I had to install OEM transmission mount and Prothane inserts in dogbones to make the car driveable again.
The most important thing is the check your oil. I sorta miss my Saturn (not).
Enjoy your new toy.