UCAS Application

Hi, I re-sat year 12 and moved college as I didn't do so well the first time round in my A-Levels but I'm in a better position now. At the moment I'm filling up my UCAS application form and want to apply for Chemistry and I'm predicted an AAC. On UCAS it tells me to confirm the institutions I've attended for study. However, if I include my previous college and results will it affect my chances in getting into my university?

Given that leaving them out will make it a fraudulent application, the answer is yes, it will make it possible for you to receive offers if you carry out Ucas's instructions to declare everything. Ucas is very clear on the subject.
http://help.ucas.com/contract12/index.html

What happens if I got a better grade the second time round? Does this override the previous grade?

Yes, it does, but you have to declare both.

How do you show that you're doing re-sits?