If you really want a good sound.
Knowing your room space and shape of the room, is the first thing.
5.1 or 7.1 ~~~ Huge difference when the movie supports 7.1
For movies, Good surround is important, you will be able to hear where the sound coming from clearly.
If you want decent sound, Stay way from HTIB (Home Theater in the box).
I would save money till I can afford real speakers with decent receiver.
A good receiver with a good sound calibration program is super important.
I would choose Audyssey calibration system over YPAO, or MCACC
Audyssey - Audio Technology | Audyssey
My 7.1 system cost me around 5K, and I love it so much.
If I have a bigger room, I will go even crazier....