I've added a paragraph under "Want to upload a file? Click Here" Are the keywords ok to use on my file hosting site? you can view it here: http://www.uploadwiz.com/WIZ4627861577 +rep for advice
They are perfectly ok - you've described your services and the technology behind it. To get more relevant ads, you may want to surround the text with: <!-- google_ad_section_start --> and <!-- google_ad_section_start --> More on section targetting here: https://www.google.com/adsense/support/bin/answer.py?answer=23168&topic=8441