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I use the Find|Replace All function quite a lot, but I will concede that it's not too hard to mess something up. Fortunately "Undo" works if you do it immediately. I think my record so far is something like "Word has finished replacing and made 82,341 replacements." (You'd never believe it, with my reputation for brevity; but sometimes I work large documents.)

Replacing quotes shouldn't affect anything else. If you want "curly quotes" you set that in Tools|Autocorrect Options, on the tab for "Autocorrect as you type," and then run (replace " with "). If you have curlies and want straight ones, you uncheck the curlies box in the same place and rerun (replace " with "). Note that you can attach a style or format to either the "Find What" or the "Replace With" boxes in the Edit|Replace screen, and if you inadvertently leave a "format" or "style" attached to the Replace With box it will get slammed on wherever there's anything you replace.

Note: the same (Replace ' with ') works for single quotes, using the same curly/straight settings in Tools.

Changing page size doesn't move the tabs, since the tab locations are a "paragraph" property. On your 8" wide page, with margins, you've got about 6 inches or so of text width. Your page number tab would likely be at something between 5 and 6 inches from the left margin. When you change to a 5 inch wide page you likely only have about 4 to 4.5 inches of text width, so that should put the page numbers "off the page," although depending on the Word version you're using the line may wrap. All that's likely needed is just to reset the tab.

If you select one line of the TOC and fix it, you can click the "format paint" to copy/paint the new tab to all the rest of the TOC lines.

Not to belabor it, but if you set up a document, perhaps called "book8x10" and insert one paragraph of each kind that you use, format it as desired and give each kind of paragraph a "style name" you can save the document as a template, "book8x10.dot" and those styles will be handily available forever.

Do the same thing for a document in your 5x8 format, "book5x8" using the same style names. Then, if you've applied the styles in your book, when you change the page setup (page size), all you have to do is click "Tools|Templates and Add-Ins," click the "Organizer" tab, close the template file on the right (that might be your book8x10.dot), open the template file for the other page size (perhaps book5x8.dot), select all the styles in the right pane, click the "copy to document" and say "Yes to All" and everything should be right in the new size.

It's actually a lot less complicated than it sounds.

And of course, always proof-read.

John