I'm lucky enough to be off to portugal next week, and I'm hearing that it's superb

i thought I'd tap into the vast knowledge of dudes in here with a couple of questions....
1. water temp: will I be alright with my 3mm (full suit)? or should I take my 5mm?
2. breaks - does anyone know of any fairly mellow breaks? I've been surfing for about 18 months, but I'm still lacking the confidence to go in when it's huge. I know my limits

3. hire cars: has anyone tried getting an 8ft mini mal into a ford focus estate?!
safe.