Super Mario DS help anyone?

I have 22 stars in Super Mario 64 DS. Some of the levels I am
having trouble on... I got a couple stars on the desert level (the one
with the pyramid, quicksand and tornado) but the last star (which you
can see on the map but not in real life) is giving me serious
trouble... also the lava level is a PITA, I got the 1st star at the
puzzle thing, but beyond that I am so fed up with that level!!!! I
finally couldnt take the frustration of those two and went back and
picked up most of the stars in the earlier levels... altho I am still
missing a few. any advice for those 2? Also after I open the 30
star room is there alot more to this game?


It's funny, I picked up a DS last year around this time with Mario
64ds and I never really got into this game (guess I kept buying a new
games forgetting about poor mario) until now, but it's taking
permanent residence in my DS until I get Metroid Prime or New SMB to
take it's place.



thanks for any advice, comments, or help!


Kevin