If you enjoy using Film then go ahead and replace the ME Super. There is a guy here however that may be able to repair yours for less, by the name of Eric (someone will sound off and point you to him). If you're willing to invest a few hundred $$ however, I would suggest a K10d. You can probably grab one for $300 or less here on the marketplace. For a digital, it's a hell of a starter camera in the used range. Others will suggest the Kx, which by all accounts is also a nice camera. Be aware however, that the digital path is a slippery one. Once you start, you won't be able to go back very easily.
Re your lenses. Most should work fine with the Pentax DSLR with the possible exception of the Sears 135. Some of them were made for Ricoh cameras and even though they worked on Film cameras, will not mount up (without modification) to the Pentax DSLR.
Either way, good luck (if you want a nice ME Super, Contact me via PM).
PS.. Make sure the batteries in the camera you have are working. If the batteries are dead, so is the meter and the camera may not function properly without it.