Thanks everyone for your help…I did switch to a Linux hosting account, and the site is MUCH faster. Thanks for the tip!
But here’s an interesting thing–since switching to the Linux account I can’t get ANY contact form plugins to work. I’ve tried a few, and none send the mail successfully. I tried WP-Mail-SMTP to try and reconfigure to outgoing mail settings, but it hasn’t done anything.
Is there any reason why contact forms would work fine in the Windows environment but not the Linux?
Thanks again for your help!