Excel 2015 annoyances

I have two annoying things happening when I use Excel 2015. Firstly if I have a sheet open, and I open another sheet, the second sheet goes behind the first. As I use sheets which look very similar I have frequently altered the top most sheet thinking it is the second one. Is there a setting to make the last opened sheet go "on top" every time.
Secondly if I open say three sheets in sequence, I cannot save/close the last two without first saving/closing the first one, then the second one etc.
Again is this a setting thing. Look forward to some replies....

Are you asking about worksheets or workbooks?
How are you opening?
How are you saving?

You are asking questions about Excel2015 but your profile refers to Office2000 - which one is it?

Hello Kevin# Yes I am asking about workbooks, and in this case with Excel 2015. We work with workbooks with generally 1 sheet, and I am opening either from within Excel or from Windows explorer. In either case the 'just opened' w/book appears behind the last opened book. I appreciate that simply clicking the minimise button of the forward one reveals the book behind, but at the expense of appearing lazy...it would be nice not to have to do this. The other issue regarding closing w/books...If I have say three books open, and look at explorer, they appear (lower left) as three preview icons, the first opened one to the left, the other two to the right. Clicking the cross to close in the two RH ones, or right-click-close does not have any effect until the left most is saved and closed, which I might not necessarily want to happen... ie save & close the third one but keep the first open.
Any ideas would be appreciated... Thanks in advance...

Thank you both for your replies. I will have to verify the version when I return to work ... Bank Holiday weekend !.
It is not on this PC.
Re The opening issue. Cant remember the last time I opened a new (blank) workbook, but the issue is
with existing books, which I mentioned in the first post look very similar.
It does happen every time I open one, and yes they do have macros( in all the files ). When I open an
existing book it flashes 'on top', to be replaced immediately with the already open one 'on top', so Im wondering
if it is a windows related issue. Will send screen shots if it helps.

I do not think pictures will help.

It may be "Windows" related. Does it happen with any other programs or is it only Excel that is afflicted?

Open a workbook where it happens and have a look at workbook level macros - only the ones that are in the ThisWorkbook module (not ordinary modules) Are there any macros there? Look for WorkbookOpen or WindowsActivate