Well, uF is 10^-6, nF is 10^-9, and pF is 10^-12, so 0.022uF is 22nF, or 22000pF
The 'metal can with 2 leads' is a crystal, and it probably won't start up with 100pF. Don't confuse a crystal oscillator with an RC, they are very different. With an RC osc. the cap charges through the resistor, so using a cap which is five times as large, would take five times as long to charge.
I don't think you have told us what PIC you are using; some have internal oscillators, which don't need anything other than configuration, and may be a better choice for you.