I have ventured into these murky waters and...
For decent HT sound, a 5.1 channel/speaker system is minimum. You can climb to 11.2.4 or more.
Good amps like the 9.2 capable Yamaha 3070 or similar are a great and economical way to go. (I have only moved on from a 3030 to a full Anthem ARC60, M525 x 2,+ M325 for 13 discrete channels). Speakers like the B&W 703 are great for dual purpose stereo and HT. I have only used Miller&Kreisel (M&K original Satellite/Volkswoofer, full set of 950 series and now full set of 300 series) speakers for HT so do not have experience in others, aside from reading about the wider range in A/V mags.
You can make a big impression with an economical 5.1 system.