I'm no expert, but I am using Google AdWords and have run into some of the same issues. First off, you can email Google within your AdWords space and the WILL answer your question within a day or so.
Second, you need to enable the "Advanced" managment feature. Sounds like you're still using the Starter controls, which basically give you no control over where your ads appear.
Once you're in the Advanced mode, create a campaign and specify a monthly budget. Google will only display your ad enough times to spend your budget - they will not go over your budget.
To get rid of the content network, do the following:
1. Sign in to your AdWords account at
https://adwords.google.com.
2. Select the box next to the campaign you wish to edit.
3. Click 'Edit Settings.'
4. Locate 'Networks.'
5. Click the checkbox next to 'Content network' to deselect this option
and click 'Save changes.'
Hope that helps!