My DS is very hot blooded. He sleeps in just a diaper. I like to call him "sweaty head". People have told me to put him in a onsie eventhough he is hot blooded but he does better wearing only a diaper and I cover up his legs with a sheet and leave his arms out. When I wake up in the middle of the night sometimes his arms or feet (if he kicked the sheet off) are cold, but his head and body are warm so I just let him be, or I snuggle up close to him and put my arms over his arms to warm them up a little before I go to sleep again.
As for the trashing around thing, my son does that sometimes and I just try and calm him in his sleep. I use to have to hold is arms and legs down (gently) for him to stop to go back into a peaceful sleep. Sometimes I just have to back away from him and give him his space. Sometimes he wants to snuggle with his blankie and not me. It is just trial and error for us.
berkeleyp - This is just what I did and it worked for us.
I still use my pillows, blankets, sheets and teddy bear (yes at 24 I still sleep with a teddy bear whenever DS will let me
). I just made sure that DS was laying far enough below the pillow and that the blanket only came up to his waist at the highest. I was afraid of myself or DH rolling over on DS but it was my hubby that informed me that when DS was next to him he didn't move all night and I found I was the same way. I feel that your instincts kick in and you are so intune with your baby that if your DH were to roll over on the baby (highly unlikely IMO) or a sheet were to go over their face you would "just know".
Also, I don't feel bed rails are really needed untill your little one starts being mobile. Even then they don't really recommed them because they baby could get stuck but I haven't gotten to that age yet.
At first you may feel uncomfortable and you will probably wake up everytime your baby's toe moves but once you get the hang of it you will sleep so much better (at least we did). All I have to do now is when DS starts moving his head back and forth I pull out the boobie, feed him, and we both go right back to sleep.
Ok, novel over. Good Luck!
*ETA* Sometimes when DS wakes up in the middle of the night sort of thrashing around I just have to put my boob next to his face and he snuggles up and falls right back to sleep. Of course that is how he falls asleep all the time.