some posts and theme missing suddenly

I was having trouble accessing my blog and my server said it was the photopress plug-in causing the problem. I deleted this file from the directory, but before I had even done that I received a string of comment approval emails dating back to the first post 3 years ago. Now, the theme that’s been up for 3 years and all the posts from the last 2 years are gone from the site. They’re shown in the server’s file management, but not displayed. Where do I start? let me guess…update to latest version?

Thanks for any help…please dumb down any instructions for me.

Sincerely,

Glenn