All depends on you personal circumstances and your ability to pay mortgage going forward... if you have decent income and low mortgage and job relatively safe then tracker is the best but if you think job / income at risk and just about meeting repayments then maybe go with fixed
Interest rates from ECB not expected to increase until end of next year at earliest so risk of interest rate hike is low...however any bank can increase their variable rate without an ecb increase in rate
hope this helps... if need further info, please advise approx mortgage and approx income and whether risk of job /income loss