regain free disk space in XP

hi friends

its been some time i dual booted my OEM Vista Premium (HP Laptop) with XP

while partitioning the hard drive i created two 4gb partitions out of the 8gb freely available. now the problem is that iv nearly stopped using vista and i just stick to xp and now 4gb space seems insufficient and the low disk space warning comes up every now and then

Could anybody suggest any method to increase the space in my local drive without reinstalling XP

OR

Any method to remove those unwanted application in Xp to free up disk space

I have already stopped system restore to regain space

please suggest
thanx