I really don't know why people are telling you to do all of the side missions, they are absolutely terrible and really should never be done unless you are trying to the god awful achievement on the 360. Seriously just stop where you are with them at this point since they take about as long as the main story line takes to do while the payoff for them is so little/insignificant in ME2 and have no benefit in ME1. That is unless you haven't been going just straight paragon or renegade, then i guess they pose a small purpose though even then it isn't the end of the world and isn't worth going through all that work if you are not enjoying the game in the first place.
As for the original Mass Effect as a whole, you kinda have to play it for the story since everything else about it is pretty average at best and that's it. It had a few working parts that made me get through it three times with the last time 100% it which made me never want to play the game ever again (so many bad side quests cannot be overstated) but really i would only recommend someone finishing it just by going straight through all of the story missions just so they can get it out of the way so they can start playing ME2. Every con you have is improved greatly in the sequel down to the characters actually showing some type of personality. I usually like to think of it as an Assassins Creed jump in quality from the first to the second.
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B8 resident lurker for 5 errrrr 6 years
Currently Playing: Mass Effect, Assassins Creed 2 (just got a 360)