One free service that can fix all of your problems is CloudFlare.
Here is what it will do for your website(s):
- Keep your site online, even when the server is down, by serving a cached version of your site.
And many more features. I have used this service and it works like a charm. It saved me 80% of my bandwidth, it made my sit 60% faster, and I had 98% less spam than before.
The best part is it's free!