Thanks for posting your question here. The quote you submitted was not an originally statement by me, but rather it comes from the ancient yoga text, The Hatha Yoga Pradipika
. Lotus pose, also called Padmasana, is a well know pose. The Pradipika does describe the pose is some detail but a more modern explanation may be better for you. You can see a picture of it here:
This site will give you all you need to know about how to get into the pose. While this pose is said to destroy all disease, it is not for everyone, and it is certainly not the only pose you need do in order to meditate. In fact, for most Westerners, I would not recommend you be in Lotus Pose at all. While it may indeed destroy all diseases, it also may destroy your knees.
Our posture for meditating should be stable and comfortable. For most people, that is not Lotus pose. Try half-lotus or just sitting cross-legged, and make sure you are sitting on a bolster of some sort. Sitting up allows the pelvis to rotate slightly forward, as opposed to sitting on the floor where the pelvis rotates backwards, which means that the lumbar looses its nice lordotic curve, which in turn can interfere with the flow of energy.
If your goal is to be able to sit for a long time in Lotus Pose, then you will want to work on opening the hips so that they can easily handle external rotation, without stressing the knees. Try the flow I give in YinSights for the hips: http://www.yinyoga.com/ys2_22.214.171.124_flow_for_hips.php
Also, try sitting on the floor whenever you can, just to keep working at the hips and lower back. You don’t have to sit in any particular way, just get on the floor and move around when you need to. Get off the couch.
Your goal of sitting for 2 hours in Lotus is an ambitious one. I don’t know of any meditation practice that would make you do that. In the advanced Zen sittings (known as sesshins) students may sit for 45 mins at a time, but not much longer. In Vipassana, one may sit for up to one hour at a time. But after 45 ~ 60 minutes, it is time to take a break and move. Walk for 10 ~ 15 minutes, mindfully and quietly, then resume sitting. If your posture is really painful, then it is okay to mindfully adjust your posture and find a new position that is doable. But make sure you are not just fidgeting. We are trying to open the body, not break it.
Hope this helps.