Oracle 10g DB Startup problem on an XP SP2 Core Duo laptop.

I have installed Oracle 10g Personal Edition on a Core Duo laptop (and then imaged to other machines), with Windows XP SP2 and have the intermittent problem of the services running (starting) fine, but the database does not start.  Once I login as sysdba I am shown that I am connected to an idle instance.  Once the DB is strated it usually runs normal from that point on.  We have tried a registry edit to the EMSTATE property under the LOCAL_Machine\software\oracle\sysman location, thinking it was a fix, however we still run into the same condition.  Is the processor so fast that the services get started before the DB comes up? Any thoughts?  We have already checked with our onsite DBA.

Thanks in Advance.