Stainless lines will be an upgrade regardless of what pads you go with.
I suspect since this is your first time out, you'll have plenty of fun even with the stock brakes, just back off on the speed a bit if they start to feel funny and they'll cool off.
Do you know how long the sessions are or how many sessions they're doing? If they're short then stock brakes will be fine I think. You're probably going to be out there with plenty of other drivers who aren't skilled on track either, so I doubt it's going to be super fast.
Just to get you a bit excited about track time, here's my last sessions of 8 (25 min each) at VIR North easter weekend.
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2010 2SS
BMR 1" Springs
Koni Orange struts/shocks
1LE rear sway bar
SRP Racing Pedals
Hurst Billet short shifter
Square tire/wheel setup
Elite Engineering Catch Can
Stainless Power longtubes/highflow cats
K&N Typhoon CAI
RPM Motorsports of Garner, NC dyno tune (421 RWHP)