I have been diagnosed with pulmonary emboli and deep vein thrombosis; sounds very serious, you think?

Absolutely. Dvt with pulmonary embolism can be life threatening. Make sure to follow your physicians advice. You may need to have a thrombophilia workup and should be placed on blood thinners.
Yes. As dr. Hanson said, a DVT with pe is potentially life threatening and potentially very serious. With proper treatment with blood thinners and appropriate follow up, the long term outlook should be very good.
Yes. Could be life threatening in fact. Take your Coumadin (warfarin) and wear your compression stockings.