I have a Epson Stylus Photo R1800 printer that I haven't used for around a year, and I just tried to print something, and I had to replace the Magenta, Gloss Optimizer, yellow, blue, matte black.

1.) Does the ink dry up if it is not used? Is there a way to prevent it from drying when not in use?

2.) Is there a way to check if there is still ink in the cartridges? The red lights were blinking above each cartridge -- should I just toss them?

3.) Is it safe to throw these in the trash or should they be disposed of some other way?