How to speed up my site (I tried other things)

My site is extremely slow: http://www.collinsfuneralhome.com/

I’ve removed unused plugins, check image sizes and added the wp-cache plugin. I’ve read about optimizing plugins but I’m not sure how to do this? I’m using the multi-level navigation but I removed the code to test the site and there wasn’t any difference.

Does the number in the cache setting expire time (3600) matter?

Any thoughts and help would be really appreciated. Thank you.