both ideas sound FUN and are fun.. main thing is to make sure your car is mechanically sound before starting any of these hobbies. i do a couple track days myself and there isnt much too it. get a helmet tires and make sure everything is running fine( brakes, fluids, tires, and do a quick suspension check). and yes you're car is a bit heavy for the track but before starting a serious track build attend a couple track events and see how they are. if your car is safe to beat it on the track try out tracking your car as is and see how you like it. me and a few friends will be going to multiple track events this year and you are more then welcome to tag along.
Now for drifting me and my buddy go to drift events and change tires all day at shannonville and let me tell you from my point of view that it is a very exspensive hobby since you run through tires in like 2-4 laps. we are going up May 20th for another event if you want to come down and check out the event and talk to the guys there that drift their cars. cars are constantly breaking and need re[airs after every event. check out son240sx.org they have a big drift community there.
hope some of my input kind of helps