By doing the Actuarial Studies course, will it equip me with the skills and requirements in order to obtain a career as an Investment Banker in the future? Or would majoring in Finance be more suitable for this?
As far as I can tell (from friends), actuarial will set you up more to do insurance, risk analysis etc. I've also heard that actuarial is the hardest of all the Commerce majors with a very high drop out rate, so even though you can do IB from actuarial you may not want to.
Important to note is that when you graduate from unimelb (or any uni really) you aren't officially an actuary as you are required to work for a certain numbers of months and then take another test. From memory it can be around 7 years from starting undergrad until you are actually fully qualified.
Actuarial is very maths (well, it's pretty much all maths to be honest) whereas finance not so much. Finance will cover some more directly applicable subjects (derivative securities etc) but you may be able to take them in the actuarial major anyway.
Either will work but it depends on why you were wanting to do actuarial and then pivot to IB after graduation.
In summary, actuarial is maths and risk, finance is Investments, Derivative Securities etc. It really depends on what part of IB you were wanting to go in to.