Yeah, the prop. driver doesn't like the nouveau kernel module. In fact, newer NVIDIA blobs spit out a warning and offer to blacklist the kernel module automatically. This, however, will probably not suffice because you'll have to uninstall the drivers and rebuild the initramfs.
Complete nonsense. All the "mighty" software center does is install the exact same driver offered by NVIDIA, only that it's already packaged into a DEB which some other packages
may depend upon, and handle the proper deinstallation of nouveau itself.
That
doesn't mean that
- you can't install a newer version directly as long as other packages don't depend on the blob from the repository (in 10.04 and later the package is called nvidia-current)
- you can't build your own DEB which exactly replaces the repo version and will leave dependencies intact
Before I made the mistake to buy an Optimus machine before checking for proper Linux support, I didn't touch the repositories for this
at all. Now using bumblebee I'm too lazy to build my own DEB so I'm sticking with the repo. The advantage of installing the driver with an NVIDIA installer is that you get fresh and most of times improved software as soon as it's available and don't have to wait for some package maintainer to build and release a new DEB for you. For older releases nothing like that will even happen, especially with a LTS release since new, cutting edge software, including drivers, will
not be backported. Lucid (i.e. 10.04) brings nvidia-current at version 195.36.24 - Precise (i.e. 12.04) brings 295.40 and Quantal (12.10) will of course bring at least 295.53 and most likely jump to 302 as soon as they're stable.
Everyone who tells you that using a GUI for installing a drivers is absolutely necessary to avoid complications is just telling you, excuse me,
plain bullshit. What's necessary to avoid complications is to learn how Linux works.
BTW, to reply to your statement that 10.04 is a LTS release, guess what, so is 12.04. Do you have any reason to stick with an LTS release?