Per Matt's suggestion, I am starting a thread for this bug (originally posted in the MC11 alpha build 18 thread). This bug applies to all versions of MC10 and 11.
First of all, I don't know what to say regarding how to reproduce it. For me it's this:
1. Install MC
2. Run MC
About 80% of the time, my taskbar will either not come out of 'Auto-hide', or it will not 'Keep on top' of MC forcing me to Alt-Tab to another application in order to see my taskbar. I have not been able to determine why it doesn't happen 100% of the time. I've tried giving focus to different aspects of MC's interface, tried resetting the auto-hide and always on top properties of the task bar, etc. Nothing will fix it aside from keeping the window non-maximized and leaving a gap between MC and the bottom of my screen.
This is a persistent bug. It's been in MC10 for as long as I can remember (all the way back during beta). I reported it a few times on each new release and finally gave up because it never acknowledged by the authors. Other's have reported several times as well.
I don't know what else to put here other than my system info. Note that I am currently running XP SP2 (release candidate 2), but this problem is not associated with it at all. All of my video drivers, my nForce drivers and my audio drivers are the latest. BIOS is also the latest.
Media Center Registered 11.0.19 -- C:\Program Files\J River\Media Center 11\
Microsoft Windows XP Workstation 5.1 Service Pack 2, v.2149 (Build 2600)
AMD Athlon 2071 MHz MMX / Memory: Total - 1048 MB, Free - 492 MB
Internet Explorer: 6.0.2900.2149 / ComCtl32.dll: 5.82 (xpsp_sp2_rc2.040610-1520) / Shlwapi.dll: 6.00.2900.2149 (xpsp_sp2_rc2.040610-1520) / Shell32.dll: 6.00.2900.2149 (xpsp_sp2_rc2.040610-1520) / wnaspi32.dll: N/A
Ripping / Drive Y: Mode:ModeSecure Type:Auto Speed:Max
Drive Z: Mode:Normal Type:Auto Speed:Max
Digital playback: Yes / Use YADB: Yes / Get cover art: Yes / Calc replay gain: Yes / Copy volume: 32767
Eject after ripping: No / Play sound after ripping: No
Burning / Drive Y: YAMAHA CRW-F1E Addr: 0:0:0 Speed:44 MaxSpeed:44 BurnProof:Yes
Drive Z: Memorex DVD+/-RW Dual-X1 Addr: 0:1:0 Speed:5 MaxSpeed:5 BurnProof:Yes
Test mode: No / Eject after writing: No / Direct decoding: Yes / Write CD-Text: Yes
Use playback settings: No / Normalization: None