Lol, the toilet issue is well documented in the first few days. You have to lower yourself down slowly and then get up verrry slowly. 
I agree, trainers are a must. I started without them and hurt the bone I broke last summer.
I'm not an expert. I've just been doing the shred - or elements of it since the end of August.
As well as the shred, I've got Jillian's Banish Fat Boost Metabolism, which I love doing - especially the 2 kickboxing circuits. The problem with that one is that its 40 minutes plus warm up and cool down so not as easy to fit in during the week, but you can select individual circuits to do. There's no weights in it either, but lots of plyometrics, so its still pretty tough.
I've also pre-ordered Ripped in 30 from Amazon. It was supposed to be being despatched on 27 December, but I've had an email to say its going to be delayed until the start of January now.
I restarted it, doing all the advanced moves a couple of weeks back, but ended up with a shoulder injury and life stress getting in the way. I only managed a level 2 shred once last week, so decided to restart level 1 this week and do a week at each level. I am adding in a couple of circuits from Banish Fat Boost Metabolism in every day as well though, because I enjoy doing that one. I also like to do the whole of BFBM at the weekends if I can.
Level 2 is hard. So I'm dreading next week. It has lots of planks and the last circuit is horrible - particuarly the chair squats with v-raises, but level 3 is great and I really enjoyed doing it. You really start to see the results of all your hard work during level 3 as well, as it all comes together and that spurs you on.
What size weights are you using? I started with 3lbs and they definitely worked on my arms, but I'm finding a much better result now I've started again with 5lb weights.
If you want to see what's involved in the other Jillian DVDs I can recommend going to an American site called Collage Video, as you can watch clips of all her DVDs on there.