Ripping Questions

[Hsean]

I'd like to ask 2 more questions about sprites, and maybe they've an easy answer like my previous one:
1) I tried to import another monster in RPG Maker 2000, but after I thought I successfully made all the changes to the picture (8-bit & 256 colors) and imported it in the game, I clicked on its the background as usual but this time in the Monster Menu the picture was like this (just a sample of the hand):

...so I thought that someone probably already edited this pic, since the borders are like that.
Do you know how can I fix this problem? I thought that maybe there is an easy way, like a program that lets you select only the "internal" picture (I mean the hand and the rest of the shape) leaving out its background, kinda like in RM2k where you can select the BG or the pic, and I was thinking about a program that lets you do just that but with the option to CUT the selected part and paste it somewhere else, so that I could save it.
I hope I explained myself correctly. I have Paint, IrfanView and Photoshop CS3, If you know how I can fix this problem with these programs It would be great.

2) My second question is about the Backdrops. I found many on this website and I saved a few, like the FFIVAdvance one. However, after cutting them with Paint, I can't seem to import any of those great background in my RM2k game. I noticed that in the RTP folder, the Backdrops are 320x160px, however I've no idea how to get that size (If I put 320px in the first, the other one becomes 170px, while If I put 160px in the second, I can import the Backdrop but It's much smaller than the other ones, with the rest of the background black).
I could go on and list all the things I already tried, but I'll just ask my question so that you won't lose any more time reading: Do you know the steps that I have to make to correctly import those Backdrops in my RM2k game?

This is all. I hope someone will be able to help me again!