First vs. Second Class RAIL

First class is nice. You get a meal and get served with tea/coffee/juice/newspaper. From my experience, I found it a bit quieter and calmer. But I do I remember one time while sitting in first class, I tried to get some rest and the guy in front of me had his ipod full blast.
However second class does good too. I'd save money by hanging in 2nd class. I would consider first class, if my journey is several hours long.

As for couchettes, I found it a bit crowded in a cabin of 3 other solo female travellers. My cabin had a small sink with mirror, beds were clean but I found the pillow really small and a thin blanket. Not really a big deal. With my luggage under my bunk bed, I did get some rest before being waked up by the train attendent for my upcoming train stop.

Second class is usually just fine- seats are still comfy, still enough room to sit, etc. As for couchette vs sleeper, i've found that it's not much easier to sleep in a sleeper than a coutchette, although you do get a little sink to freshen up and a bit more room (4 to a room instead of 6). I do have one exception to this, although it was about 5 years ago so it may no longer be this bad. My family and I took a sleeper from Florence to Paris. We traveled 2nd class because there were 5 of us and it was much cheaper. Big mistake- it was during the time of the heat wave in Europe that people were dying from, and second class had no AC. Truly awful. I'd be interested to hear if that run has AC yet or not.

Clarification: Couchettes have bunks for either four or six people. Sleepers have beds for either one, two, or three people.

I have never had a sleeper car or taken an over night train, but if you are taking some short trips 1-4 hrs then 2nd class is fine and will save some money. 2nd class is just like any airline seat with a little extra room. It is also easy to go for a walk and streatch the legs. You can also always walk down to the beverage car and they have more room in there with tables to sit at. I have always traveled with a back pack so it is easy to pick it up and take it with you to the dining car. When you are sitting at your seat do what Rick says to do and that is some how clip your backpack/bag to the railing so that someone cannot walk away with it very easily. I also always put my bag so that I can see it based on the direction that I am sitting. Dont put it behind you. Just a precaution.

Thanks. We are traveling with backpacks. I think I'll go with second class. I'm not sure if we have any super-long trekks yet, but if we do...I figure from what I've read I can just reserve a sleeper on a night train right there in Europe. We will be there during shoulder-season and there are only two of us, so I am hoping (cross my fingers!) that seats and sleepers won't be sold out during that time.

Night trains on popular routes can sell out weeks in advance even during shoulder season. It's best to book those well ahead of time.