FIRST, MAKE SURE TO BACKUP YOUR DATA! See my FAQ*:
http://www.macmaps.com/backup.html
If all you have is one partition, and no other external drives are attached, and no digital camera media is inside any attached printer or media card reader, and the file is in there and won't trash after booting into safe mode, boot into single user mode.
To boot into single user mode, hold command and S key keys down simultaneously.
at the prompt type the following:
rm -r ~/.Trash/*
ls ~/.Trash/
if there are still files inside you may have other data corruption which needs to be dealt with. Let us know if this is the case.
- * Links to my pages may give me compensation.