why can't I scroll through my list of songs in my phone

When I opened the latest version of iTunes and plugged my iPhone 4 up to the macbook, I clicked on 'my phone' (on the left-hand side) and then went to music. I had gotten a message when I was trying to snyc that there was not enough free memory to sync so my goal was to eliminate some music off my device so that I could. when I went to the music tab on my phone, not on the left hand side in my library, it pulled up the many windows (i.e. catagory, group, album, etc.) as it has for the last several updates. The problem I had was that I could NOT scroll though any of those windows to check on un-check groups or albums, etc. First I had a problem with the 'disappearing' scroll bar(s) just navigating through the music screen because they kepy disappearing and wouldn't come back unless I stretched the entire window....only then would the scroll bar(s) show up so I could see all the windows. Then, once I got to where I wanted to go (say albums) there was no way for me to scroll down through said albums to check or uncheck songs.

Having said that, how am I supposed to put music on or take it off my iPhone4?