Recently whenever i go for interview and after all the usual talk comes the salary negotiation part ... and I'll will always state my expected salary in percentage & the HR  person will always look at the expected salary column and jokingly say things like " u are asking xx % ? How did you manage to come up with this number ? "  

What gets me is the way they say it like I'm a complete fool and they are the ones who what is the "proper job increment value is" 
Pls help got interview again on Monday... honest answer only & no bashing me pulak ...ok

if its stated under consideration on jobstreet for a job i applied for, is it a sure thing that i will get called for an interview?

Yes, they are pretty similar questions, but requires diff method to answer.

1) Will have to depend on your personal view of success. Maybe sitting in an MNC office high up, with the title Director is how you define 'success'. Or maybe simply achieving a target set - is success in your terms. This have to be based on your personal POV.

2) Again, same as above. Varies from invidual - success factor could be your motivation, your will, persistence, high adaptability skills etc

3) What do you want to achieve in these upcming years? 3 years' time - Executive, 5 years - Assistant Mgr, 7 years - Manager? Or 3 years - Ass Mgr, 5 years - Mgr, 7 years - Deputy Director?

Well this question test how ambitious you are, and check whether you have an aim. In any case, since you know interviewers like to ask these questions to you, plan your answer first before attending

First job: served abt 1 year, left bcos higher salary, widen job scope & 5 WD/week
Second job: company down sizing, so get retreched lor. I also served there abt 1 year only
Third job: company politic n dun like working enviromeny, served abt 1.5 years
4th job: nothing to learn, boss dun care what i doing. Sometime even no meeting or discussion in a month. So i jump job when got great offer by 5th company
5th job: retrech due to plant shut down, i also serve 1.6 year like that

When i tell my friend or collegue i had served 5tth company, they are "mata besar" look at me. I had attened interview few time b4, interviewer always ask me why I change company so frequent.. they seem not so buy me my explanation.