1. Solution 1 is correct and You could either do it directly by practice Or Could use NFA to DFA conversion Algorithm to see that. . Solution 2 is wrong and to check that You can use "Null string" as a counter example.
2. Does every 'DFA equivalent' of any NFA has same starting state??
No, Not Necessarily. In case of Epsilon Move Free NFA (NFA without Epsilon/Null Move), You could say that 'DFA equivalent' of any "Epsilon free NFA (NFA without Null moves)" has same starting state.
But in case of Epsilon-NFA (NFA with Null Moves), Starting state of Equivalent DFA is the Epsilon Closure of the Starting state of that NFA. So, Starting state May or May not be exactly same (But It would definitely contain the Starting state of that NFA).
For example, You could use NFA in your diagram. In the given NFA (It is Epsilon-NFA), Starting state is A but in the Equivalent DFA (Solution 1), Starting state is AB.