So a Win7 64bit 2.4Gh 6GBDDR3 500GB Hard drive that has DDR3 SDRAM Intel Corei3 should do it?
That would be a nice replacement based on what you’ve said so far. It kind of depends on whether or not you would make changes in what you store if you were to get a much larger drive. Users who go for 1Tb drives store a lot of video files for example. Or maybe they want to partition a 1 Tb into separate drives for different purposes.
I think you just want to make this as painless as possible. Since you already are comfortable with Win 7 and the drive is larger than what you have now, it would be a good upgrade for you. It is the way I would go. If you went with the Win 8.1 system, you would have a significant learning curve to climb, plus you would be buying a larger drive than you really need. None of that is really bad, but you just have to be prepared to make adjustments with that choice.