I use Mobil 1 Fully Synthetic, does the job nicely, and I change it every 5,000ks
And I use the Oil Filter that fits the RB30 - VL R31
Put your car up on some car stands, and get a large bucket can etc.. just something to catch about 5-6ltrs of oil.
Go under the car, there will be a sump plug at the bottom of the sump, it will just look like a nut stuck in the side of the engine, get a shifter or rachet and undo the bolt.. make sur ethe can is underneath the bolt directly as oil will pour out straight away, drain the oil for a good 30mins, make sure its all out.
Take off the oil filter, watch out because that may be full of oil as well, and let that drip empty into the bucket.
Get the new Oil Filter, rub oil around the seal, and screw onto the engine block.
Put the sump plug back in.
Fill the car up with oil.
Start the car, go for a bit of a squirt, bring the car back, chuck a bit of carboard under the sump to check if there are any leaks.. if not.. your done!
I think thats about right.. someone correct me if im worng - thats how I change my oil anyway.