To view index.dat files just open them with notepad or word...(most of what you see won't make much sense)

To delete index.dat files: Boot to "safe mode with command prompt
Type cd\ then hit the enter key (this will take you back to the root directory C [Linked Image]
Then at the c:type del index.dat /s then hit the enter key

Be warned that this will delete all index.dat files on your system