I've got an 03 1.6 16V dynamique+. It had always been abit lumpy on idle, would jump from about 500rpm to 700rpm and back down again. (bought from new by the way). It didn't seem to have any lack of power, although sometimes she could feel like she really couldn't be bothered. Due to the fact it's a French car and other people had similar problems , I thought ths was perfectly normal, so did nothing about it.
On Tuesday of this week however, I went out to the car, started her and got the shock of my life! She sounded like a tank and was as lumpy as f**k. I asked on here what the problem could be as she was obviously badly misfiring. To cut a long story short , the nice kind lads on here told me they thought it was a dodgy coil. I had it towed to the garage and it turned out it had blown TWO coils. (Center two). I got her back the same day and couldn't believe the difference. She now idles really smoothly and is now very quiet. She is actually better than she was when new. I have come to the conclusion that she had always had a problem that just wasn't that obvious. The response on the throttle is better than it ever was too.
It does sound to me that you have a similar problem, and would say (as the guys have said) that you probably have a fucked coil (coil pack as they are different on the 1.2s).
When it comes to the clutch. I find that sometimes mine just does not want to go into reverse. Seems like something is in the way, but if I pump the clutch pedal a couple of times she will then go straight in. It does sound like a common problem and could just be a case of the gear linkage needs adjusting. I'm not going to bother with mine as it only happens very rarely, but if it happens regularly to yours I would get it checked out.
Oh and the popping sound you are describing, sounds like a misfire, which again points towards a dodgy coil or leads/plugs.