are you using levers to install the tire? if you are, stop. you should be able to do it without a lever (on most tires, not all).

FWIW if I inflate my 700/23 front to 120 psi it will go back donw to about 100 in the course of a week or so. I usually run it at 100 and it stays at 100 for a really long time. I probably reinflate once a month. if I'm going on a long ride or working out alot I will keep em at 110 and inflate em once a week. not telling you what to do just trying to give you an point of reference.

when I was first getting into bikes (after a long bikeless hiatus) I ruined a bunch of tubes trying to install them with levers. then a good friend showed me how it is really done.

when you say the tubes "popped" does that mean they actually went bang or just that they no longer hold air?