What should I do about my TV / Blu-Ray player Sound issues?

I have a 32” HDTV in my bedroom, hooked up to a basic Blu Ray Player (among other things) via HDMI cable. But when I watch movies on it, the dialogue sound is really soft but the effects and music are loud.

So I found out that the solution lies in being able to control the sound channels – such as center and peripheral channels – as with a sound system. But I have no idea what to get that would remedy this.

Do I need a full system? Do I need a receiver? Can i get by with just a Sound Bar? I have no idea, so can anyone advise me?

My budget for this is about $150.