If i file for annulment based on marriage fraud, how will that affect his 2 yr greencard?

If you think the marriage was fraud, you will need to report it to the USCIS. With a 2 year GC, he can remove conditions with a wavier on his own. If you report it, it will but up to the uscis to do something about it.

Not at all unless you supply evidence to USCIS and then it will be up to them to decide what, if anything to do about the two years and whether to allow the conditions to be removed.

Not quite true. We'd need to know more about the grounds for the annulment based upon what the OP declares is 'marriage fraud'. If the OP suggesting that there was something that made the marriage fraudulent, there are a number of cases where the alien would not be eligible to self-petition. For example, if the marriage is annuled, on the basis that the alien was not eligible for marriage (another spouse) then it would impact his immigration status. Likewise, if the OP was coerced into marriage for immigration benefit, and a court annuled the marriage as a consequence, the alien would not be eligible to self-petition. Bear in mind that in order to self-peition, an alien must present a divorce decree, or in the case of annulment, a court order annulling the union. What is contained therein, as to why the court honoured the petitioner's request to annul the marriage would become a part of a self-petition.

diaddie are you saying that if i file on the grouds of tricking into marriage to get his GC and then left then would he still be able to self petition and get his 10 yr GC?

i think she is saying it depends on the exact circumstances.

It depends on a number of factors. One, yes, of course if the USC notifies USCIS of the alien's disingenuous intentions and supports the allegation with evidence, then any petition to remove conditions filed by the alien would be closely scrutinised and he would be left with the onus of demonstrating to the USCIS' satisfaction that the marriage was bonafide. However, in the case of a divorce, and I would imagine so too in the case of an annulment, if a family court terminates the marriage and it is articulated why such termination occurred (in the case of an annulment, language in the court order to stipulate why the annulment was granted), then it would be difficult for the alien to contest if he is required to present such document with his petition to remove conditions to show his eligibility to self-petition.