How to Ace GRE in a month?

Dears,
This is Darshan from Dubai and I work as a Technical Consultant for an IT firm. I am a post graduate in computer science graduated in the year 2007 with 3.5 years experience in IT.
• Bachelors of Electronics engineering 2003: 1st class 78%
• Masters degree in computer science 2007: 2nd class 63%
• (6 month thesis with good score and a paper published)
• 3.5 years of work experience until now
• IELTS Score : 7.5 out of 9 overall (7.5 listening, 6.5 reading, 6.5 writing, 8.5 speaking)
• GRE?

I am setting up to sit for the test in the month of December 2010. I have full month fulltime to prepare. I am pretty confident to ace it
Questions
Do you think I could ace above 1300?
How are my chances for a good university?
Should i have to take the GRE general test or a specific subject test?
opinions and suggestions please!!!
Cheers