I somehow don't think you are going to absorb sufficient lead to do you any harm whatsoever.
You simply won't be in contact with enough of it for long enough periods of time.
Sorry can't believe that fact, I've known plumbers handling the stuff very directly and in large quantities for years without any problems whatsoever.
As to cleaning leaded windows, I'm WFP now but prior to that I would use a sprayer with one of the cheap solutions in them (Tesco do a good own brand one, as do Wilkinson) a quick mist and buff clean with a scrim....Though now I would use the large Unger microfibre cloth as they are far better than scrim for this type of work. (Haven't used other makes, so I'm not saying the Unger ones are the best out there!)
Regards,
Ian