I have Fedora installed and would like to try another Linux flavor, perhaps OpenSUSE. Can several versions of Linux be installed easily to be selected on bootup with GRUB? Thanks.

Best bet? Install VirtualBox (or some other virtual service) and install other "flavors" in virtual machines. Easy to do, easy to use.

You can dual-boot but it may be more pleasant to work with (multiple) virtual machines (and they're easier to get rid of, too).

Hope this helps some.

I have used "virtual machines" at school but I don't really understand them -- in terms of advantages / disadvantages / system requirements or execution speed.

Advantages:
- You can run many systems simultaneously, quite handy for different uses, for example simulating networks. So no reboot to try something in a different OS.
- You don't have to partition the harddisk for installing a new OS, they are installed into container-files. To get rid of them just delete them.

Disadvantages:
- While VMs are OK to have a quick look at a distro, if you want to know if that distribution id compatible to your physical hardware a VM is of no help.
- Because of the virtualization of several components those might be slower (especially true for the graphics card) than your physical hardware. So no real gaming in a VM.

System requirements and execution speed:
- On a modern machine (means with a CPU that features hardware virtualization) you should see only a slight loss in performance, except, as stated above, when it comes to graphics performance. To run more than one or two VMs at the same time modern multicore CPUs are the way to go, no problems here to run six VMs (loaded) on a six-core machine, may be even more, haven't tried it yet.
- On older systems without hardware virtualization the system will be slower, sometimes to a point where virtualization makes no sense.
- You have to have a look at the available amount of RAM in your machine. If the host OS needs 1GB to function properly, and the guest OS also, you will in fact need 2GB of physical RAM.

Virtual machines are very nice for distro hopping, because you don't have to resize partitions (which always carries a risk).

If someone wants to sample different distros, as opposed to use them regularly, VMs are an excellent way to go.

VMs are regularly used in production environments. Many webservers we access regularly are actually virtual machines running in a virtualized environments on datafarms.

Assuming that you have enough RAM to begin with, as TobiSGD cautioned, RAM may not be an issue for distro-hopping. When I distro-hop with VMs, I am running the VM or not running the VM; I'm not running the VM while I'm doing my day-to-day computing.

I run Ubuntu and Slackware (and WindowsXP), and I boot all of them with Ubuntu's grub2. I sometimes add even a third distro to the mix. I do it like this:
Install XP to the first primary partition.
Install Ubuntu to second primary partition.
Create swap on third primary partition. All distros can share swap.
(You can have 3 primary plus many logical partitions. So I go ahead and use the 3 primary partitions).
Install Slackware to a logical partition. When I install Slackware, I opt to not install lilo, since I will boot Slackware with Ubuntu's grub2.
I then create a logical /data partition for all my data that all distros share. This way each distros home directory is on that distros root partition. This prevents potential conflicts between all the hidden config files stored in the home directory between distros.

So if you want to use both Fedora and Suse, install Fedora first and set it's grub to boot the system. Then install Suse and either don't install Suse's grub, or install Suse's grub to it's root partition.
You should then be able to boot fedora and add Suse to Fedora's grub menu. Consult Fedora's documentation for how to do that since I am not familiar with Fedora, so I can't give advice on that.

There are Linux skills that can be learned by reading a few short guides and then there are Linux skills that will take more than one attempt to master.

I have plenty of Storage so I have,

CentOS 6
Mandriva 2010
XP Pro
Fedora 15
and Two installations of Fedora 14 on the same computer.

I also plan on installing Mageia soon and might try to install Debian just to see what the installer is like. As long as you have room you can install; I think it is as many as 16 ,O.Ss with Grub Legacy.This figure might be for Lilo actually.

Usually it is relatively easy to boot two O.Ss with Grub but problems are encountered with more than two. It is usually less problematic to chainload O.Ss off of the first Linux Distro installed.

For a newbie I would recommend a live disk because it is so easy or if this is a good time to study a subject that other related subjects must also be delved into, Dual Booting is the way to go. The usage of a Partitioner and a Bootloader are essential skills in the Linux experience that have to be learned to progress to higher levels of understanding. Just a Dual and not a Multi-booter is usually pretty easy and risk free.

Just to say - the Ubuntu installers were pretty good for me, and correctly recognised my WinXP, as well as *another* Ubuntu that was there, and added them to the GRUB menu automatically. VERY convenient

Hi Davejjj;
I've got a multi-boot system with 3 linux distros and windows. The solution I use is to have a common data area (not /home) which is available to all the linux flavors. Each distro then has its own /home tree. This resolves difference problems with distros which use different versions of programs.

One caveat to be aware of in this method is that you must insure that all the distros use the same UID for each user or access to the common data (in /common) will not be possible for all. In each distros ~/ I have replaced the data directories (documents, music, etc.) with symlinks to a corresponding directory in /common.

Tom