Replying to Computer wiz HELP

I have a one year old lap(Dell) top right now that works perfectly i just want more room because i am running out with music and other stuff and I don't want to delete stuff to make other space.

-I want to get a bigger hard drive and replace my smaller one.  from 60 GB to 100 GB.
-I would also get more ram,  adding 1GB to my already existing 1 GB.

My question is to get an operating system which would most likely be VISTA am i able to install it on my computer after just installing the new hardware?   I am not sure if i can do it that way or if i should bring it to someone, which is another option.

I would appreciate any advice or experience opinions(Other than telling me to get a MAC you idiots) about any of the stuff i have posted from the upgrading to vista or good or bad idea.  Any random comments are great too.

Thanks, ericpbp