Operating system comparison
Back in the day, MAME was developed to run from DOS and users had to use a Windows frontend or Mame32 to get it running in Windows. From MAME v0.37b15 onwards, Windows became the MAME developers' platform of choice.
Running an older version of MAME from pure DOS will allow you to run a large number of games at a higher speed than would be possible on the same computer running Windows.
These days, a DOS system can take a lot of work to set up correctly, due to the lack of software support from motherboard and device manufacturers. For these users, a Linux install makes a lot of sense.
Each of these four operating systems has advantages and disadvantages.
- Boots to your Front-End faster
- Stable, rarely crashes
- Can display on an arcade monitor without special hardware
- Using batch files (.bat) a high degree of customization is available (including menu creation)
- Low cost
- No shutdown requried
- Newer hardware may not work under DOS (such as TV - Out and USB) without special software.
- Command line interface, only suitable for experienced computer users.
- No longer supported by Microsoft. FreeDOS, a free, open source variant of DOS, is still supported.
- Fewer front ends are available for DOS.
- Purple MAME - a good (but outdated) site on getting DOS Mame running on a cab.
- Dos Mame Support - another good site on getting DOS Mame running on a DOS cab, including getting sound cards working and memory management.
- How to make DOS Menus - a site showing how you can create menus in DOS (great for boot menus).
- Free. (Windows adds about $100 to the cost of the cabinet; Linux is free.)
- Open Source
- More likely to support newer technology than DOS
- Less Hardware. Linux does not require nearly as much processor as Windows (especially later versions of Windows); thus it can run on a slower CPU and with less storage space.
- Complexity. There is a steep learning curve to Linux.
- Fewer frontends available
- Fewer emulators (NonMAME) available.
- Inavailability of some tools. Some of the supporting software for MAME does not have a Linux port.
- Limited to the older (native) games. Most new games are written on Windows, and not on Linux; so to play these new games requires not only Windows, but also a rather powerful machine.
- Boot time. No noticable difference. You can get a faster boot with a cut-down Linux says (elvis), but it is also true that you can tweak Windows a lot, too. Tok found Linux to be slower both in boot and shut-down. Quarters says you can compile your own stripped-down kernel for lightning fast boot times.
- Speed. Games do not appear to play noticeably faster, nor slower on Linux versus alternatives.
- Low software maintenance requirements. (negligible occurrence of viruses, trojans, spyware)
- Higher initial cost
- Fewer choices for front-ends (only 1 cabinet friendly front end available)
- Several major encoder manufacturers do not create Apple compatible encoders
- Fewer choices for gamepads and hackable controller parts
- Fewer emulators have been ported to Mac OS X
- Much smaller homebrew application development community
- Mame runs much slower on PPC
- Huge market share advantage
- Software generally is developed primarily for Windows (MAME and most front ends included)
- Much larger selection of software
- Security holes (however less relevant in a stand-alone environment such as an arcade cabinet)
- Higher cost (Windows can add $100, or more, to the cost of building an arcade cabinet.
- Boot time. No noticable difference. You can get a faster boot with a cut-down Linux. But it is also true that you can tweak Windows a lot. 
- Can run both DOS programs and many Windows programs
- Lower Hardware requirements (98SE is the recommended Windows flavor for legacy machines)
- No longer supported by Microsoft