Question 1: Is there any way to umount a device when mtab has been altered?

Details:
I did something impulsive and dumb (editing my /etc/mtab). Now I cannot umount the partition (I only altered the options a specific mounted partition). Whenever I try a umount, i receive an error message saything that mtabe is stale.

Question 2: How do you give a regular user permissions to read, write, and mount a device (and preferably keep those permissions every time my computer reboots)?

Details:

The device is a partition of a secondary IDE harddrive I have installed.
I want to mount /dev/hdb5 in /mnt/shared. It is entered in fstab.

Subquestion: Are there any fstab options that would allow me to set permissions (rwx) for a mounted device/folder?

I have repeadly tried changing the permissions for both the device and the folder using chmod, chgrp, chown with no luck (NOTE:I have tried this both before and after mounting).

Don't know if this will help, but i'm using Gentoo, kernel 2.6.11-gentoo-r3.

You can try the umount -f command to force an unmount but I do not know if it will work with a stale mtab. And now you know to never edit the mtab file.

You haven't provided enough information but if it is a FAT32 filesystem then linux file permissions do not work. Use the umask=000 option in the /etc/fstab file. BTW a search of the website would of discovered the answer in no time flat.