You could do Rasika West End - close to Georgetown but better parking. You could always walk to Georgetown after if its a nice evening.

Daily Grill in Georgetown has valet parking. I also think the watefront is nice. Someone already suggested Bangkok Joes (they have happy hours all week -- Sun. throught Sat. from 4-7 so if you get their before your dinner reservation -- have a nice half-priced drink).

I would add Founding Farmers Fishers to the list...the outdoor fountain is lovely and you'll be in the swing at this recently reopened hot spot.