Bent lines: Typical problem of a weak power supply.
Nearly all consumer TV sets exhibit this problem to some degree, most cheap ones really significantly "bloom" and more so, bend vertical lines, especially on the bottom 1/2 of the display on the far left and far right of the screen, the more white there is displayed on the screen. (White takes the most power as all 3 guns are firing at full intensity, lessing the amount of power available to control geometry and other things)
It might be fixable to some extent by replacing every electrolytic cap, including the large filter capacitor (that is not part of a normal cap kit), but probably one or more transistors are not performing as well or other components may be weakend due to age.
Ken Layton however might have more info on this particular model.
Tear: Older arcade monitors typically don't sync well with new computer VGA cards (and sometimes certain arcade game boards) and can show tearing. Sometimes cap kits can help, but many times you may not be able to fix it from what I've read.