I noticed that after you open a virtual instalation it is Ok to close the player. Is it possible to open a Vm without the openeing the Player?
yes - read about vmrun.exe in the documentation
Would this be the correct command even on VmPlayer?
vmrun start "C:\Documents and Settings\<user>\My Documents\My Virtual Machines\WinXP\WinXP.vmx"
AFAIK this should work - for me it works like that