Academic Search Complete only allows PDF versions of articles, but my computer can't open them.
There are also HTML versions of many articles and sometimes only HTML versions, but you are right, the vast majority of articles are available in PDF version only. Unfortunately, you can only limit to full text or PDF full text (in advanced search), not to HTML full text so whether any come up in your search will be random.
There is an easy solution, however. You can download free software for your device that can read PDF documents:
- Adobe Reader (link below):
- MAC OS
If you have an iOS device (iPad, iPod, iPhone) you can use these free apps:
- Adobe Reader (link below)
- iBooks (comes with the system)
- Bluefire (link below)