Any time the brake system is opened up, it should be bled. In fact brakes should be bled EVERY 2 YEARS to prevent corrosion from building up and damaging expensive parts.
I doubt you messed anything up by pushing the brakes w/ the caliper off.
I use and recommend BG DOT 4 brake fluid. It has a very high dry/wet boiling point and I get it at a discount, but its stil pricey.
Ive also used "store brands" which also work fine.
The most important thing is to get all the air out of the system.