I have been having a lot of fun lately with building my new HTPC. It is based upon my old Gaming Rig, ASUS M2N-SLI Deluxe w/ AMD Athlon XP 3500+ (64-bit) w/ 2GB RAM and a EVGA Geforce 7900. I added a Hauppauge HVR-1800 for TV tuning, it supports NTSC, ATSC, and clearQAM tuning. I put all of this into a new case, a Coolermaster CM-282 which has a built on front panel LCD and Remote Control by SoundGraph.
With the Soundgraph LCD and Remote you get the Soundgraph iMon/iMedian software, iMon provides controls for the Front Panel and Remote, iMedian is Soundgraph's HTPC front-end, and it isn't horrible...but it isn't complete and the performance is not what you would really want. My biggest issue with the iMedian software is that as I delete/add files to my Hard Drive I would need to rescan to update the database. And the scanning is beyond slow for iMedian. So I began looking for alternatives, SageTV, BeyondTV, Meedio (now Yahoo Media Center or something like that)...etc. I found a lot of these did some things better than iMedian, however, overall they were not what I wanted.
Finally I came upon a free HTPC Front End software by a guy from New Zealand, the software is named GBPVR. It not only does everything as well/better than iMedian, it also has a built in TV Tuner that is very feature rich, with built in Electronic Programming Guide (EPG). Now GBPVR still has its issues, however, the developer of the product is extremely willing to help and fix issues. I filed (well opened a support thread on) a bug with DVD Special Features and he had a test fix for me within a few weeks. The issue was that some Special Features are in 4:3 frames and the software was not getting that data and rebuilding the frame, so the video was being stretched. Anways, he fixed that very quickly and he seemed eager to improve his product. For this I gave him $10 USD. As a retail product I would have to pay far more for this but, it is just a donation. Also, remember my main complaint from iMedian, having to rescan all the time, well GBPVR seems to not use a static db but, rather reads the current directory structure. So no phantom files or missing files.
If you, like me, are looking for a good HTPC front-end, I would highly recommend you look at GBPVR.
