I generally use Windows Media Player Mobile rather than HTC Album. I believe both take advantage of the hardware acceleration drivers. Is that true? I didn't want to pay for Coreplayer, so I ruled that out early. I loved TCPMP on my Palm OS devices, but was never really happy with it on my TP2. I suppose I should figure out how to install it again as a backup for when I'm not playing .mp4.
To encode my videos, I'm basically choosing iPod Touch/iPhone presets. The TP2 can handle higher resolution, but I'm happy with the result and I don't need to recode the videos for my wife to watch on her Touch. For TV programs recorded on my XP MCE desktop, I use MCEbuddy freeware to strip the commercials and recode. I happen to use Handbrake for DVDs (after ripping with DVDFab). There may be better options, but since it's working for me, I'm not about to mess with it.