Need help in translating warnings

I just switched from Lunar Pages to Go Daddy to host my blog because LP decided to wipe out my blog for no special reason.

However, the transfer did not go as smoothly as it should have.

For example, after finally getting my site online, I received the following warnings.

Warning: array_keys() [function.array-keys]: The first argument should be an array in /home/content/c/a/r/carlosmiller13/html/wp-includes/widgets.php on line 686

Warning: Invalid argument supplied for foreach() in /home/content/c/a/r/carlosmiller13/html/wp-includes/widgets.php on line 686

Warning: Cannot modify header information – headers already sent by (output started at /home/content/c/a/r/carlosmiller13/html/wp-includes/widgets.php:686) in /home/content/c/a/r/carlosmiller13/html/wp-admin/install.php on line 12

Also, if you look at my site, you will see warnings at the top of the page and in the right sidebar.

I have no idea what these mean nor how I can resolve them.

Can anyone help?

Here is my site.

https://carlosmiller.com/