Not a great deal of help, but have a look at this thread
, which explains these files. It may give you some ideas to work on. Presumably you know that you are running SQL server - what do you use it for? It sounds as though, for some reason, you are getting access errors, which are creating all these files.
Don't forget that whatever the size of the file it occupies at least one cluster on your disk so even if the files are tiny they can soon add up to quite a space. The good news is you can delete the files.
Don't worry about the Search Indexer - it may be that this is trying to index the other files as they are being created. But, normally, indexing your disk is a good thing.
Hope this points to a line of investigation. Good luck!