[FX.php List] Displaying & Updating comments

[AC]

I'm fairly new to FX, PHP and HTML.
I need to do the following with a comments field;
    - display it on the web
    - pass it as a hidden value to be entered into the database
    - pre-populate a textarea with it again to be put into the database

If I just display the comments then text like" <B>" makes the rest of 
the characters that follow bold.
I tried htmlentities() which worked but gave me "&#8221" instead of a 
quote.
Now I'm using str_replace() to substitute the text "&#8221"  back to a 
quote.
My problem with this is it still doesn't cover things like multiple 
spaces and carriage returns.
I also have issues when a user enters weird quotes, I can't seem to 
write those to the database at all.

How should I be doing this?