New to Ubuntu.. but better late than never

After a day long fight with installing the latest version of Ubuntu .. finally I'm up and ready .. and running !!! (though very tired to run actually ) :P

Installing Racket v5.1.1
post downloading the file-racket(i86_64).sh ,
run
change permissions - chmod +x  of the file
./file.sh
 
then its asking certain options which are :


Do you want a Unix-style distribution?
  In this distribution mode files go into different directories according
  to Unix conventions.  A "racket-uninstall" script will be generated
  to be used when you want to remove the installation.  If you say 'no',
  the whole Racket directory is kept in a single installation directory
  (movable and erasable) unit, possibly with convenient external links
  into it -- this is often more convenient, especially if you want to
  install multiple versions or keep it in your home directory.
Enter yes/no (default: no) >

I say NO.

Then .. it asks ,
Where do you want to base your installation of Racket v5.1.1?
  (Use an existing directory.  If you've done such an installation in
   the past, either use the same place, or manually run
   'racket-uninstall' now.)
  1 - /usr/... [default]
  2 - /usr/local/...
  3 - ~/... (/home/dhall/...)
  4 - ./... (here)
  Or enter a different directory prefix to install in.
>

Then, whichever options I enter.. It doesn allow me to install it ..
it says

Error: cannot write to "/usr/local".  (or for that matter any option I enter. )


SO THE SOLUTION IS .. .to use sudo ./file.sh  !!!
then choose
YES
and 1 respectively
after which it asks
Do you want to install new system links within the bin, lib, include,
man, and doc subdirectories of "/usr", possibly overriding
existing links?
you say YES..


downloaded !!! :D


for SVN

post uploading the public key on the server...


run the repository ---- check out

svn co svn+ssh://rishabh.dhall@popl.iiit.ac.in/home/rishabh.dhall/svn/popl

which ever folder u run it .. creates a popl directory ...   then do stuff !!! (svn basically )