Thanks to everyone again for the info.

Here are my thoughts:

• Fly to SIN (overnight there)
• bus to Malacca (1-2 days)
• bus to KL (1-2 days)
• fly to Langkawi (4-5 days)
• fly back to SIN (overnight)
• head home

We may alter the days a bit, but this seems to be relatively straightforward from the transportation side of things.

We arrive late (11pm) to SIN that night, so do you have any suggestions for a hotel near the bus station (for Malacca)? Prefer a Sheraton, Hilton, or Conrad...but not if they are more than a 10 minute cab ride.