Congratulations on your new bike! I just got my '01 250 EXC on Friday. It is also my first KTM after 20 years of Kawasakis for enduros. I am using Maxima Super M oil which I switched to from Kawasaki oil since it is supposed to be cleaner burning and have less drool out the exhaust. I never used Torco oils and don't know anyone who does so I can't help you out there. I guess thats not so popular here, I've never seen it for sale at the shop.
W.E.R. and Enduro Engineering both make good aluminum skidplates for this bike, as well as other aluminum protection items. Lots of people I know use these companies and I've only heard good things.
For hopups, so far I am starting with a softer seat foam, aluminum bark buster hand guards, and a DCI relocater which moves the black box to under the gas tank, where it is more protected and also allows you to adjust the steering to turn tighter if you like.
After this I am planning on getting another silencer (lighter weight!)but I am not sure what kind is good yet. Maybe the FMF Turbine Core II.
Also on my wish list is front and rear disk guards, braided clutch hose, radiator guards, and maybe a new pipe.
OK now I am up to $500 in goodies I am wishing for, but my bike usually gets whatever it wants
Keep us posted on how your setting your bike up and how you like it!