Very sudden odd high resource usage

Hello,
I was informed via my host that the two files below are causing high resource usage on my site:

/wp-content/uploads/bartpef/pebuilder3110a.exe
/wp-includes/js/prototype.js

The first is a file, which I can take down. I have no idea what plugins or themes use /wp-includes/js/prototype.js If anyone could help narrow down this issue, I would appreciate it.

I’ll be able to tell you what versions of plugins and themes I have as soon as my host resolves another issue.

Thank You!