Yes, framerect editing is one of the simplest things you can do. If the collision needs be unchanged, then this is also optimal.
Balfrog you say? Let me see what my function listing says....
It looks like his framerects start at 0x479039. The framerects are grouped in bunches of four, Left Up Right Down, specifying sides of the rectangle that make the frame. To make one taller, make the Up rect smaller. You may need to just rearrange everything on the sheet though if it needs to be as big as you say.
If you don't even know the basics of changing values with assembly then you should read carrotlord's guide I believe. Anyway it's the stuff that looks like this:
Code:
00479061 |. C785 78FFFFFF>MOV DWORD PTR [EBP-88],0
0047906B |. C785 7CFFFFFF>MOV DWORD PTR [EBP-84],30
00479075 |. C745 80 50000>MOV DWORD PTR [EBP-80],50
0047907C |. C745 84 70000>MOV DWORD PTR [EBP-7C],70
That is frame 1 (not to be confused with the first frame, frame 0). Have fun. Remember all values are in hexadecimal.