I'd say that's a good start. As you listen more and more and find out what services you like best, antennas cut for those frequencies will allow you to hear more. For example, a good antenna at 154mhz is pretty lousy at 42mhz. A good antenna for CB won't hear as well as a good FM broadcast antenna, etc. But go with the discone and take it from there.
Last year I bought a used Icom R-7100 receiver and I LOVE IT!! I can listen to CB, FM broadcast, TV audio, and the local police and fire departments. I've also heard the audio link for KOA radio out of Denver on 25mhz (I'm in Wisconsin), a TON of NOAA weather stations at 162mhz, all the ham bands (6 meters, 2 meters, 220mhz, 440mhz), and recently was listening to the Tennessee State Patrol on 42 mhz. What makes it especially nice, is that you can tune in the AM, FM, wide FM, or SSB modes, not just in FM like many scanners. When I get tired of listening to one thing, I can listen to something entirely different by simply spinning the dial !
Way cool if you ask me.