[chaley]

For problem 1: reading/not reading.

1. Create a custom column of the type you want (yes/no or text w/ or without/fixed set of values -- you choose)
2. Using the search box, find all books with the tag "Read"
3. Select all the found books. Press 'E' to bring up bulk metadata edit.
4. Go to the custom metadata tab (the middle one). Select the equivalent value for 'Read' for your newly made column.
5. Press OK.
6. Now use search to find all books with the notread tag. Repeat steps 3-5, using the correct value for notread.

For problem 2: copy of tags. You must have made a "column made from other columns." The behavior you describe is how these columns are supposed to work, immediately computing a new value based on the changes made in referred-to columns.

Instead, you want a copy of the tags. To do this:

1. make a "column containing text, like tags"
2. Select all books.
3. Press 'E' to go to bulk metadata edit
4. Go to the third tab, search & replace
5. Set the search mode to "regular expression"
6. Set the Search field to Tags
7. Set the destination field to #whatever_your_column is
8. Press OK

This will copy the current set of tags to the new column. From this point on, they are completely separate.