I would agree with all the previous posters, that is don't be put off by the alarming articles and photos of epic waiting times. I read one or two of these and in the comments accompanying them there were plenty of people saying "rubbish, I was through in 20mins from plane to taxi rank" and so on. I think such doom articles, especially on news websites generate many clicks and are therefore encouraged. Aside from peak times, when several long haul flights arrive at the same time, it's probably quicker than normal!
I would have no hesitation in asking for wheelchair or buggy assistance to help glide my way through the process if I were you, take advantage of the offered facilities. This will allow you to make a good start on your well-deserved holiday.