Hi Geoff, welcome to the forum
It's difficult to say what you could do for your old Konica but the short answer is: probably very little. Sadly. Colours can be tweaked and adjusted in software afterwards but if the camera is suffering with electrical or mechanical issues it's almost definitely not worth repairing.
In terms of replacements, the Panasonic you mention is a great camera but it does have some stiff competition from a few other competitors. To be honest it may well come down to how much you want to spend but the cameras below are the front runners in this field (with the Panasonic for comparison)...
Panasonic DMC-FZ38
12.1MP, 27-486mm (18x) zoom, 2.3 fps, HD video (720p), 2.7" screen. About £250.
Canon Powershot SX20 IS
12.1MP, 28-560mm (20x) zoom, 0.7 fps, HD video (720p), 2.5" screen. About £300.
FujiFilm Finepix S200 EXR
12.0MP, 30.5-436mm (14.5x) zoom, 1.6 fps, VGA video, 2.7" screen. About £300.
Olympus SP-800 UZ
14.0MP, 28-840mm (30x) zoom, 10 fps, HD video (720p), 3" screen. About £300.