thanks for responding. I did Step 1. Step 2 I did using Akeeba backup kickstart, Though I restored it under xamppfiles/htdocs, not under xamppfiles/apps/joomla/htdocs.. But I didn't manually remove Joomla! files first as shown. I haven't had to do that before. Joomla example site works fine under /apps.
On my other laptop I have several development sites working fine under xamppfiles/htdocs. I restored one using akeeba under this directory as explained above. It restored successfully, but when I go to localhost/sitename in browser, it downloads the index file.
I've compared htpd and various other config files between laptops and they're identical. PHPAdmin works, Joomla works, so it's got me foxed... Let me know if you need more info.