my rec for a straight stitch only machine would be a singer 15, 66 or 99.
for a zigzag capable machine, a 401.
look on these sites to learn more, collector sites, not selling ones.
http://ismacs.net/singer/models.html#householdhttp://www.needlebar.org/cm/index.php?cat=59
don't get confused too much about the das and numbers yoou see behind the model numbers, it ususally designates how it is motored either with a foot pedal, knee bar, a treadle, an internal or external drive belt motor...
needlebar 15's are in the folder "improved family" (IF)
I'm not totally sure what the 'real' definition of a computerized machine is... I think of the ubber high end machines... talking in the thousands of $'s as being compuerized, you can actually hook them up to your computer and do extra things... embroidery I know, possible other things....
Then I think of some of the higher end but not outrageously expensive... upper hundreds of dollars as being 'computerized... they don't link into your home computer but they have electronics in them... memory with stitches and such, sI know that magnets should be kept away from them because of 'boards' ....
Then there are just electric machines... I think of those as working on a toaster, if your brave enough to do simple wiring then you would be comfortable opening one of those up and tinkering around with their inards... basically just run by electic.
The ones I love are the ones that have no wires on them at all, the treadles and handcranks... all metal ones, they are the ones that will last a lifetime and won't hurt you uless you drop one on your foot... they do have memory in their stitches just like the fancy ones....you just don't turn the dials

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