Precise should be quite stable now. I'm using it without problems, but I have only a couple of PPAs. I suggest that you try the commands in the following list, originally posted by oldfred. Use sudo for all the commands.
Originally Posted by al.adab
# This will reinstall if not current. (from my chroot procedure which does not have sudo on every line,
# so use the sudo -i first).
#if not chroot use: sudo -i
apt-get autoclean # only removes files that cannot be downloaded anymore (obsolete)
apt-get update #resync package index
apt-get upgrade #newest versions of all packages, update must be run first
#would upgrade you to the latest kernel in the repositories
#dist-upgrade is also able to remove existing packages if required
# fix Broken packages -f
sudo apt-get -f install
dpkg --configure -a