As an (almost!) doctor, I will say we should ALL be having regular check ups!
(that's a pap smear, once every two years, and a breast examination by your Doctor at the same visit. And check your own breasts monthly or so)
Personally - I too struggled with the pap smear thing.. no, it's not the most pleasant thing in the world but it's a hell of a lot more comfortable than CANCER!
As someone else mentioned - the more you can relax your legs (think happy thoughts!) the less uncomfortable it feels. It should NEVER be painful, always tell your doctor, a good doctor will change positions/instruments and make sure you are not in pain!
As for breast examinations - personally I check for lumps every day in the shower, but that's just me, I'm a paranoid med student. Remember, breasts can be naturally lumpy (especially around your period) but if you are worried, GET IT CHECKED!
Breast cancer is tricky, but the earlier it is picked up, the better the outcomes!
And as for cervical cancer - it is one of the few almost entirely preventable cancers in the world.. it grows slowly, so two yearly pap smears is enough to be able to pick up the pre-cancer lesions... if these are noted, you are just monitored closely for a while, as many disappear by themselves. If they progress, simple laser treatments (under local anaesthetic, in the gynaecologists office) can be performed and you are CANCER-FREE!
If you NEVER get a pap smear, and leave it for years... you might find you have a really advanced case of cancer.. then you would need a hysterectomy (goodbye chance of having children, hello early menopause), and possibly chemotherapy and radiotherapy. And yes, cervical cancer CAN spread to the lungs, the bones, the gut (anywhere!) and yes, it CAN kill you.
So ladies - GET A PAP SMEAR EVERY TWO YEARS (the first being 2 years after you first have censored)