You were nearly there:
Jw1e1 = {{16, 832}, {32, 3150}, {64, 12237}, {128, 48212}};
J1 = ListLogPlot[Jw1e1,
PlotMarkers -> (Style[Framed[H, RoundingRadius -> 20], Red]),
Frame -> True]

The nice thing here is that you can play around with `RoundingRadius` and that longer/larger text markers will be properly framed as well.
J1 = ListLogPlot[Jw1e1,
PlotMarkers -> (Style[
Framed["Longer than strictly necessary", RoundingRadius -> 20],
Red]), Frame -> True]

Driving it home:
J1 = ListLogPlot[Jw1e1,
PlotMarkers ->
Framed[Style["Larger than \n strictly necessary", Large, Red],
RoundingRadius -> 20], Frame -> True]
