Ok, so what you should do is send that to your host. If they are somewhat knowledgeable in MySQL then they should be able to read that ok and see that it's not a software issue with those queries taking so long.
Basically, it's saying that it's using the Primary key index on both tables and it's only having to examine 1 row to find the result. If the last number was large, then we'd be looking at an issue since that means it has to examine multiple rows to find the result.
There most be other things going on with that MySQL server contributing to the slowdowns. If you're on a shared server then that could be part of it.
