The "blank" startup entry may not be anything to worry about. I have a similar entry in MSCONFIG and remember reading in a different forum that it may be nothing to worry about. The following, more detailed explanation (which I just found) may be helpful:http://ask-leo.com/why_is_there_a_blank_en...up_entries.html
I followed Leo's instructions (at the above link) and found that my "blank" entry was associated with 'MISAggregator'. Further research showed that 'MISAggregator' is part of the McAfee security suite, which I did have installed on this computer in the past. I thought that I had previously removed "everything McAfee", but evidently not.
Just follow Leo's instructions at the above link to see what program/process your "blank" startup entry is associated with and go (Google-search) from there.
The "blank" startup entry on this computer has been there for some time now and has caused no problems.