Are there differences between "regular" stereo speakers and home theater speakers?

No. Speakers are speakers. They all have woofers, tweeters, etc. The difference is that home theater speakers are typically all "matched". This means they have been designed to work together to produce sounds at the same levels and tones. If you had a home theater setup with five different brands and types of speakers the sound would be totally mis-matched as people walked around a room, or planes flew around your head. ... more