Under normal circumstances I'd advise installing Visual Studio and all available service packs only - hotfixes are "quick fixes" for problems, which are then rolled into service packs when they have been thoroughly tested with all the other hotfixes in the service pack.
You shouldn't normally install a hotfix unless your copy of Visual Studio exhibits the specific problem that the hotfix addresses, and it is vital to you that the problem is fixed. (Because any hotfix may introduce further instability and bugs, there is no point installing it unless you know you need it)
You'll find a (hopefully) complete list here (near the bottom of the page) though, which may help you locate any hotfixes you feel are relevant.