I am aware that asking which distro is best is like asking what type of coffee is best. But my wife just got a new Macbook Pro for her birthday (thanks to her wonderful husband) and I'll get her old Acer laptop with an ADM C-50 processor running at 1 GHz and 8 GB of RAM.

I have been using Puppy (Tahrpup) for a couple years on an very old IBM Thinkpad and really like Puppy, and it runs great on this jalopy. But I imagine that the Acer can handle a more robust distro like Mint or Ubuntu. I have some familiarity with Ubuntu from a few years ago and very little exposure to Mint, but from what I've heard and read, it can be used "out of the box" without any modifications. I don't customize or modify the kernel or anything like that, or even use console for that matter. I don't do any high-end operations like video editing or gaming. Mainly I just need it for documents, spreadsheets, email and surfing.

Or should I just stick with my beloved Tahrpup?

With 8GB RAM, that should handle just about anything, even given the netbook like processor.

Try booting to Live CDs or USB of the distros you are interested in. That should help you make some first-hand comparisions.

Stick with what you like, just because you have a lot of ram doesn't mean you have to run another distro.

(But if you want to try something else, take a look at AntiX MX, http://antix.mepis.com/index.php?title=Main_Page )

I would plump for something like Xubuntu, LMDE with XFCE or Debian with XFCE. Now I have to admit that I am running Debian Sid with XFCE on my machines but I do so because XFCE is light enough not to get in the way but has things like real transparency which can make working on a smaller screen better (a transparent terminal window over a web browser when typing commands from a tutorial, for example).
I have always been a bit wary of Puppy after reading a lot of posts asking how to do this and that and getting the impression it is a very cut-down distro to the point that some things could be missing (I ahve used it in a VM and from a USB boot and it didn't change that impression). So I would go wit ha full distro but probably not a more modern desktop environment like KDE, Gnome or Unity as they may just suck some cycles from the processor.

I'd vote for sticking with Puppy. After using it for a couple of years, you'll be used to its little ways. Why start learning something else? The last time I reviewed it, I wrote "In terms of configuration, Puppy is far ahead of Debian-based distros and comparable with SUSE or Red Hat." And, unlike some people who dismiss it, I've tried several versions over the years.

I thank all respondents for your quick replies. I still have to copy files from the Acer to my wife's new machine, so it will be a while before I have to decide on a distro. I'll consider all options at that point, and appreciate your input.

Please indulge a couple newbie questions. 1. What is the difference between MATE and Cinnamon, and what advantage does one have over the other? 2. Do I have a choice in desktop environments? 273 recommends XFCE which suggests that I have other options. Or am I misunderstanding the concept of desktop environments? I don't recall having any choices in desktop environments when I installed Tahrpup.

I prefer MATE, but I made that decision a couple of years ago and can't itemize the reasons why. A web search for "mate cinnamon compared" will turn up a number of reviews and comparisons.

In response to your second question, you can have as many desktop environments/window managers installed as you wish, and switch among them whenever you wish. Multiple DEs/WMs can coexist quite happily on your HDD. Slackware comes with six DEs/WMs out of the box. You are not restricted to the default DE/WM.

I normally use Enlightenment on my Mint box, but occasionally switch back into MATE.

There doesn't tend to be a choice of desktop environment on install unless you use a disc called something like "advanced install" -- most installers just install a default. However, once you have the system installed you can install lots of desktop environments and choose between them on the login screen.
What you could do is do something like install Linux Mint with MATE and install Cinnamon and XFCE and try them all out and see which feels to perform the best. There will be benchmarks out there and I'm sure one could find a list showing which desktop environment is supposed to be faster but I tend to find when it comes to desktop environments that unless there is a vast difference in speed between them (for example comparing, on old hardware, Ubuntu's Unity [slow] with LXDE [faster]) the difference in speed is often really a case of personal perception. For (a bad, but can't think of a better one right now) example if there are fancy effects when opening a window it may seem to some that the DE is faster because there's always something going on and no "wait time" but to others the time it takes to play the animation is "wait time" and the DE feels slow.
Sorry if that's a lot of possibly contradictory sounding information but it comes simply down to recommending that you try a few DEs and decide what you like best.

Most distros have a default desktop, but will have a variety that can be installed from their repos.

(Basically, the more 'bling' a DE has the more 'grunt' is needed from the system.)

To answer your two questions about desktops:

1. When Gnome version 3 came out, a lot of people felt that it was inflexible and seemed to be designed for a tablet rather than a conventional computer. Cinnamon is a modification of Gnome 3. Clem takes the innards of Gnome but replaces the actual bits you see to make it more traditional. Mate is a fork of Gnome 2, created by people who preferred a more radical solution. Cinnamon is a bit bigger, a bit fancier, and needs hardware graphics acceleration.

2. In theory, you can run any desktop on any Linux. In practice, it's best to stick with the default - that's what most of the developers were using and what most of the downloaders stick with, so that generally works best. With alternatives, sometimes (Xfce for SUSE, whenever I've tried it), useful bits have got left out. Sometimes (Xfce for Fedora), useful features are missing because they were written to use components of the default. Adding your own choice, taken from the repository, and reconfiguring the distro to use it, can be easy and successful or can lead to a world of grief.

Puppy comes with a heavily customised version of JWM - Joe's Window Manager. I didn't think much of JWM in other distros, but Puppy has greatly improved it.

If you want to read about desktops and window managers, and see what they look like:
http://www.renewablepcs.com/about-li...-gnome-or-xfce
http://xwinman.org/

Didn't I mention that I'm a Linux newbie? I don't comprehend that high-tech, arcane, Linux developer terminology.

'Bling' = uneccessary extras.
'Grunt' = CPU power.

'DE' = Desktop environment.

Regards...