If I might add something... As an alternative to TMPGEnc, there's a plugin for Premiere (that also runs as a stand-alone app) called bbMPEG and it'll allow you to create MPEG-1 & MPEG-2 files of just about any resolution & bitrate directly from Premiere. It also has presets for VCD, SVCD and DVD files.
The quality of the resulting MPG is about the same as what you'd get from TMPGEnc but it's slow. The advantage is that it will save you a step (going directly from premiere to the resulting file). If you've got plenty of time on your hands (I often start transcoding to MPG just before going to bed) then you can use this instead of TMPGEnc.