You do not have root access to your machine, or you don't want to pollute /usr, you can install python beneath your $HOME. Paste this into your shell to do it in one step:
cd wget 'http://www.python.org/ftp/python/2.4.2/Python-2.4.2.tar.bz2' tar jxf Python-2.4.2.tar.bz2 cd Python-2.4.2 ./configure --prefix=$HOME/local make && make install export PATH=$PATH:$HOME/local/bin #put this in .bashrc or similar python -v
The last statement above should print something like:
Python 2.4.2
If not, something's wrong :)
You shouldn't have trouble with this if you can grok the above.