You don't say which model of Panasonic you have, but you can shoot in many formats and still produce video that's editable in Premiere Elements:
1) Shoot only in 1920x1080. HA and HG mode should shoot in this Full AVCHD format. (You'll see slightly reduced quality in the lower bit rate settings, but it's up to you if it's still at an acceptable level.)
2) Shoot only in 50i or 60i mode. Do not shoot in 50p or 60p mode is you plan to edit in Premiere Elements.
AVCHD footage produces terrific quality video, when you've got your project set up properly to work with it. But it can take a pretty powerful computer to work with it. We recommend a good quad core or i7 computer for best performance with this format.
Once one gets beyond pixel x pixel Frame Size, and FPS, the other modes (with the same general specs.) usually refer to the Bit-Rate of the recorded file(s), with a higher Bit-Rate yielding higher quality, but at the expense of larger files.
I would follow Steve's advice on Frame Size and FPS, and then choose the mode (within those parameters), with the highest Bit-Rate. The editing experience will be the same, but one will need slightly more HDD storage space for the files themselves. Also, and very important, follow his advice on matching the Project's Preset to the specs. of the files produced. That is why he listed certain specs., as there are Presets available to match those. If you choose a general mode, that matches a PrE Preset, you will be set for smooth editing.
Also, and depending on your particular model of camera, pay attention to the Audio recorded, and if, for instance, it allows you to shoot in DD 5.1 SS, and you choose that on the camera, be sure to also select that when choosing the Preset.