It sounds as though you might've been scammed. You can download various types of files with LW but there's no special 'video access'. The only official site for download of LW is www.limewire.com
Where did you get your version of LW & how much did you pay for it? The basic version is free & the Pro version costs $18.88 USD for 6 months of updates & email support. If you bought from another site, have a read through the 2 threads below. The first has info about membership & scam sites, the second has info about obtaining a refund from a scam site.

http://www.gnutellaforums.com/showthread.php?t=28751

http://www.gnutellaforums.com/showthread.php?t=44499

If you were scammed, you should contact your bank/CC company & report this, ask if they can cancel the transaction (depending on how long ago you paid).


If you're seeing porn in video downloads, you can always follow the instructions in the link below
Direct instructions to eliminate porn from results

Also, look up a file before download with Bitzi. If the file's been rated then you'll see other people's opinions about it. It can help to stop the download of misnamed files!
How to use Bitzi