#1
I'm trying to play this tab:

http://www.ultimate-guitar.com/tabs/s/starting_line/drama_summer_ver3_tab.htm

However, there are some chords which are very difficult (and in some cases) not possible to play where the G string is held on the 7th fret during every chord. I'm not sure how to play this because my capo won't work unless I use it to bar all the strings (If I put it lower on the neck it'll just fall off). Am I interpreting the tab wrong, or do I need to buy something that'll hold that one string for me?

Also in the 3rd chord there's a (3) and I'm not sure what that means as well.
#2
Option 1: tune the B string down 3 semitones and play it open whenever you have to play the 7th fret on the g

Option 2: otherwise just practice... and practice and practice...

I'd advise option 2 - it will sound better and it will improve your guitar skills
#3
there is such a thing as a partial capo. altho i would try to play it without one.
#5
Yeah, that's more than doable, it's actually fairly easy, you just need to work on stretching your fingers.

EDIT:

And the (3) could mean a lot of things, different people use it differently. Sometimes it means you don't actually play that note, you just kind of hear it anyway. Other times it means you don't play it the first time but you do play it the second time. Other people use it to mean it's a pinch harmonic, but I doubt that's what it is.


My Guitars:
Fender Mustang.
Yamaha FG-413SL.