Wow, that was a lot of questions!
I have a few answers for you:
Yes, you can use any 4 channel radio. I have even seen someone using a 4 channel stick radio ( the type with a steering wheel ) to control their truck.
Speed controllers are a matter of choice, I have used with success the standard Tamiya TEU-101BK on several of my trucks. They are budget priced units, there are better out there but it just depends on how much you want to spend.
Brushed or Brushless ..... This one has been a debate for a long time.
From personal experience if you are looking for speed and power brushless is the answer but this opens its own can of worms. They require their own special type of speed controller. So if you wish to go brushless and have a sound and light kit you will need some Y-cables for the receiver plug-in leads so you can split the throttle signals from the receiver to the sound unit and to the brushless controller. I had done this with my Globeliner / Red Bull racing truck as below, but was not using the sound kit but the Tamiya Electrical Kit (now discontinued):
This was successful combination but removed it as it was not good for the shows and displays that our club puts on as it did take a bit of time and space to get speed up.
Hope my ramblings have helped!