Problem with quickmask

i'm not exactly sure how to post pictures or i would, but here is the problem in a nutshell...when i use quickmask, i enter quickmask mode, highlight what i want to select, go out of quickmask, inverse selection to get what i selected, and press ctrl-j to put what i've selected on a new layer, but every single time its opague..when i try deleting the excess or putting my selected area onto a new layer, it becomes about 50% opague..i've checked all my opacity settings, there all fine, i've reinstalled my photoshop, restored all defaults..completly deleted my adobe directory then reinstalled...but it still does it...if anybody can help it would be much appreciated...i know there are other ways of getting selections other than quickmask, but it is one of the easiest and most precise way of selecting an area that i know of..if you can help please reply here or add me to your msn(everybodyyea@hotmail.com) or your aim(master michael18)

Have you checked to make sure you are using a 100% black brush to make your mask? If it's not 100% black the selection will be transparent.