If you're trying to avoid paying for parking, the Smart Way Bus has a stop here at the airport and can take you to/from Blacksburg, Christiansburg, and Roanoke.
I always arrive 35 mins before take off.. with enough time to check my bag, roll through security with tsa pre and get to gate before boarding starts.. You can't do that at many other major airports.
The bus from the parking lot to the terminal does not run as advertised. Plan on walking. They have x-ray for checked baggage now. TSA lines are short but many travelers inexperienced & cause delays.
Security is rarely a problem at ROA. If you give yourself plenty of time, there is free Wi-Fi provided in the terminal for your pre-flight entertainment.
security can be a pain in the ass. I had to wait 15 minutes for their female assistant to show up and search me because I had an unidentified hard drive in my bag (camera) and almost missed my flight