< displaying as & l t ; and apostrophies as question marks

i’m thinking of moving from mt to wordpress, but have quickly come to lament the jump. I imported six years of entries on over to wordpress only to find that every ‘ had become a ? and every time I used html in a post it now displays fully on screen. Posts that used center tags now display center tags and all links have been rendered useless. Is there a find and replace function in wordpress? Is there a box I can check somewhere so that apostrophies don’t display as question marks? How do I make the links in my posts into links again without having to edit a couple thousand entries.