I could not find a camcorder with that model number on a Google search. If you can link to the specs online, that would be helpful.
JVCs can be troublesome to work with as they often save to a file format called .MOD. If this is the case for this camcorder, there are workarounds -- but MODs are notoriously challenging for virtually all video editors.
If, on the other hand, this model records video similarly to the JVC GZ series camcorder, you may be able to use one of the project presets in version 8 to work with it.
This is the link. The camcorder looks very good but I note your concerns re file format. This link may be helpful
But it looks though it is a MOV type file - if I am reading it correctly.
That would be the GY-HM100, Andy. Not the GM-HY100.
And it looks like it records to a number of formats and codecs:
60 Hz setting: HQ mode:1920 x 1080/59.94i, 29.97p, 23.98p,
1440 x 1080/59.94i, 1280 x 720/59.94p, 29.97p, 23.98p
SP mode: 1440 x 1080/59.94i, 1280 x 720/59.94p, 29.97p, 23.98p
50Hz setting: HQ mode:1920 x 1080/50i, 25p
1440 x 1080/50i, 1280 x 720/50p, 25p
SP mode: 1440 x 1080/50i, 1280 x 720/50p, 25p
Th challenge for you will be figuring out which mode you recorded to and then finding a project setting in Premiere Elements to match it!
In all, I'd recommend, for PAL video, you shoot in 1920x1080 25p and use the Hard Drive Camcorder setting for hi-def video.
As I say, JVC cams tend to march to the beat of their own drums, so I can't make any guarantees. But I'd experiment with those specs first.