Re: checking grammar
1. As I read it, "Let's (or Let us) hold our hands together" does not mean I hold your hand while you hold his hand, etc. It doesn't mean I take your hands in mine. It means we each hold our own two hands together. I'm not sure if this is what you mean.
2. The comma doesn't work there -- use "and" instead.
So I suggest either: Let's join hands and open our eyes and our hearts or "Let's each clasp our hands together [in prayer?] as we open our eyes and our hearts."
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.